Artifact-like system for monsters that applies a new set of stats on top of an existing monster’s stat block. The monster is not G_UNIQUE, but only one of it can spawn in a game.

A simpler solution would be just to add unique monsters to the monster list and figure out a way to allow these monsters to spawn randomly.

Add a system of “hell curses”. When you enter a demon lord’s lair, you are afflicted with 2 random curses, which stick around forever until the lord is killed or bribed off.

You can receive at most six curses over the course of the game, requiring you to defeat the lords of the first three lairs you encounter. Further generation of lairs does not add any curses.

A non-comprehensive list of potential curses is:

• healing potions heal only half as much HP
• your speed is knocked down by 2
• your AC is deducted
• your spellcasting failure rates increase
• you are randomly inflicted with confusion every 50 turns or so

A demon lord who occasionally summons demons (or some other sort of minion) and, when killed, will possess the body of one of his minions, so you need to kill all of the summons before he can be finally killed.

Allow for gas clouds of different types (confusion gas, hallucination gas, etc) by passing an additional argument to create_gas_cloud.

Magic bookshelf dungeon feature, which is heavily inspired by and is functionally similar to the TNNT swap chest, but only involves spellbooks instead of all items (and is not itself an object).

Looting while standing on it gives you a feeling you should put a book on the empty shelf, and if you do, you magically find other books on the shelf. You can see the identities of these books but do not permanently learn them if you didn’t previously know them. Once you take a book from the shelf, it vanishes.

Left up to the implementor whether the books would actually come from other players like the TNNT swap chest does (in which case it might end up filled with low-value or common books; if so, there are various ways this could be mitigated such as the shelf not accepting a book type it already has, or adding in randomly generated books) or whether the books would just be a pool of random ones selected at the start of the game.

An additional possible detail is that you can only see books on the shelf of equal or lower level than the total level of books you yourself have put in. So if you put in a level 1 book, you will only see other level 1 books, but if you then add a level 3 book, you will see books of up to level 4. Or, you always see all books, but only books below this threshold show you the spell and others appear as “a spellbook”. identities

Alternative Necromancer role, because its implementation in SLASH’EM winds up being a rather halfhearted version of Wizard with some elements of Priest and Archeologist. Note: This was written for a hypothetical variant that does not have a Necromancer role, rather than as an update to SLASH’EM’s.

• When playing as a Necromancer, dying monsters may drop “soul” objects, which can then be collected by the player.
  • Souls only exist as an object for the purpose of occupying a space on the map before being picked up. They are weightless and do not actually occupy space in inventory, nor can they be stolen after being collected. A Necromancer can have an unlimited amount of them.
  • If a soul drops adjacent to the player, it is automatically collected.
  • Souls drop 100% of the time from monsters the player kills, less for monsters that die otherwise. Never for monsters that kill themselves.
  • Monsters ignore souls and cannot pick them up. (There is room for an extension where certain undead like a barrow wight or a lich can collect souls to become more powerful, but that is not required for this.)
  • Souls vanish after being on the floor for around 10 turns or being moved off level, preventing the player from sitting back while pets or conflict mop up a large crowd of monsters and then obtaining all their souls with no effort.
  • Souls can also be offered on an altar to gain alignment points.
• Souls are used to fuel the casting of necromancy spells, an entirely new spell school. Necromancy spells consume some Pw like normal spells, but also consume souls, and generally are more powerful than non-necromancy spells of the same level. Various spell ideas:
  • Reanimate creature: which consumes a soul of some creature and reanimates a corpse of that same creature, bringing it back as a pet. (It may be flagged as undead, if the variant supports this).
  • Soul blast: Consumes multiple souls and produces an attack whose power is proportionate to the total monster difficulty of the expended souls.
  • Empower undead: Temporarily buffs all nearby pets, scaling up with the more souls you expend. This is intended to be one of the primary ways a Necromancer takes care of enemies, so it should be a pretty good boost.
  • Spell which consumes 5-10 souls of one monster type and create a tame monster of that type without needing a corpse.
  • Spell which consumes souls to regain HP or Pw.
  • Spell which infuses your weapon, armor, or other gear with souls, making it more effective for a time.
  • Spell which consumes souls of one species and polymorphs you into that monster.
  • Charm undead: Tames undead. Low cost compared to general charm monster.
  • Create wight: Works like reanimate creature but the resulting creature gains level-drain abilities.
• A good guaranteed starting combination of spells for the Necromancer might be reanimate creature and empower undead, since this will enable them to kill monsters, bring them back as pets, and boost them with the souls from more kills.
• Most undead (at least the mindless undead) generate peaceful to Necromancers.
• If desired, there could also be an “amulet of necromancy” which, when worn by non-Necromancers, causes souls to drop (less frequently than they do for Necromancers) and enables the hero to cast necromancy spells. However, not many other roles would be non-Restricted in necromancy spells, and any Lawful hero would be harshly penalized for casting them.
  • In order to avoid this being a useless item for Necromancers, it could improve soul drop chances for them.
  • Non-Necromancers wearing the amulet might also be limited in the amount of souls they could have at one time.
• If desired, Valkyries could be able to collect souls natively, but the only thing they can do with them without penalty would be to offer them on altars for alignment points.

The system may want some simplification since it may be clunky to have the player navigate through menus to choose souls from all the different ones they have accumulated. Possibly, souls from a given species just combine, so you would be shown something like “souls of gnome kings (12 total monster levels)”. An extreme simplification would cut out the entire soul-storage system and just replenish Pw when you collect one.

In order to add variability between different games, at the start of every game, “theme” objects and monsters are selected, which are outsizedly likely to generate. For instance, one potion type becomes the “theme potion” of the game, and then 10% of all randomly generated potions are that potion, and a wand type becomes the “theme wand” and 10% of random wands will be that wand.

Three theme monsters are picked, one low level, one medium level, and one high level. The probability for them generating when a random monster generates should probably be lower than 10%.

Wearing rings that correspond in appearance to wands double, augment, or otherwise enhance those wands’ effects, including possibly turning a beam into a cone shaped blast.

This could also extend to drinking potions with matching appearances to worn rings, such as drinking a ruby or emerald potion while wearing a ruby or emerald ring.

Make alchemy recipes randomized per-game and consistent with a game, by doing the following:

• Initialize a N by N matrix at the start of the game, where N is the number of different potions in the game besides water. The matrix provides a lookup for what the constituent potion types in the appropriate rows mix to combine.
• Basic alchemy practices don’t consult the matrix, for instance, dipping a cursed potion into something always causes a blast, and dipping a potion into another of the same does nothing.
• Nonmagical potions are possibly excluded from the reagent set, the result set, or both. Most likely the reagent set if both source potions are nonmagical - it doesn’t make sense to mix nonmagical juice with booze and wind up with a magical potion of enlightenment. But it may also not make enough sense if combining two magical potions produces a nonmagical one.
• The number of entries for a given potion type in the matrix are proportionate to the generation frequency of that potion. So there may only be one specific combination of potions which produces polymorph, whereas many things produce sickness or fruit juice.
• Hardcoded rules like could be enforced on the matrix if need be, but it’s probably better if players don’t have an easy known path to mass produce full healing or gain ability.

This system gets rid of random alchemy results entirely, but does not necessarily get rid of the chance of an alchemic blast or failing and turning into water or evaporating. Possibly these could be removed, so that the player is incentivized to try and mix together as many potion types as they can to discover what they produce and find interesting combinations.

A list of known alchemy recipes could be added to the discoveries list so the player can use it as a reference.

Replace the current Basic-to-Expert skill system with a skill tree. Each role is given affinities for skills in this tree, which represent how easy it is to for them to enhance that skill. The baseline value for an affinity is 100. The lower an affinity number, the better it is for that role, because enhancing a skill costs (some base cost * affinity / 100) skill points. Skill points are awarded on each level up.

The end result is a system without arbitrary skill caps, where anyone can theoretically become expert in whatever they want, but if it’s something they’re unsuited for they’ll have rendered themselves unable to become skilled in much else.

Replace the whole speed system with the one from Tales of Maj’Eyal, another roguelike. This has a strict concept of a “global speed”, i.e. a number of movement points you are given every global turn. Every possible action has an associated movement point cost, which allows for things like zapping a wand to take less time and be done more frequently than making a melee attack. This gets rid of the weird existing system where, in ToME terms, your most recent action defines how much global speed you get, particularly if riding is involved.

One way to start implementing this is to have all the action functions that currently return 0 for no time taken or 1 for time taken to instead return a bitmask of all types of actions taken: “moved”, “attacked”, “cast a spell”, etc. Then the main loop code that handles these return values deducts movement points corresponding to the slowest action in this bitmask.

A new take on a Bard role, generally themed around leading a party of other adventurers through the dungeon, with some other additional ideas:

• The bard and healer cannot both be focused around petmongering, so one of them would have to change. Most likely the healer, as the bard’s traditional abilities are only good on pets.
• Instead of the standard little dog or kitten, the bard starts with a “party” of 3-4 player monsters, who are randomly chosen from other roles.
  • This would make the primary strategy focused on having the party do the fighting for you, letting them level up, providing them with weapons and equipment, and not letting them die.
  • Healers and archeologists, and possibly tourists, don’t make very good additions to the party, and so should perhaps be ineligible.
  • Party roles could be randomly chosen from distinct sets of “strong melee fighter” (Bar or Cav or Kni or Val), “ranged combat” (Ran or Rog or Sam or possibly Tou), and “spellcaster/cleric” (possibly Hea or Mon or Pri or Wiz). These could also just be hardcoded.
  • The party will not start with the full starting inventory of their respective roles. They will generally have the same weapons and armor, but will probably not have any of the scrolls, rings, wands they normally start with, and starting spellbooks should be either eliminated or unrandomized. In other words, you shouldn’t be incentivized to slaughter your allies for their stuff.
• Healer strategy should shift away from petmongering - the easiest way to do this is change the protection formula in such a way that the protection racket doesn’t exist; so that the player isn’t incentivized to keep XL as low as possible until they can buy protection.
• Difficult for Healers to find a new niche. (Avoidance of combat is an option, but dtsund’s Class Overhaul Proposal calls for Archeologists to fill that niche). Perhaps something that focuses on pacifying monsters by healing them, but this has issues: you shouldn’t be able to ‘‘tame’’ by healing since that turns Healers back in the direction of acquiring lots of pets, and most monsters start at full HP and don’t need any healing.
• Bards (and probably all players) should be able to equip their pets by #looting them, or a similar mechanism. (This would also apply to mounts.) Intelligent monsters will prefer player-given items above all others and will never willingly replace them for other gear. Possibly make this behavior dependent on options, because some players may want their pets to be pragmatic in their gear choices.
• Player monster pets should perhaps not be able to detect curses.
• Songbooks, + class items which contain a song that the bard can learn.
  • Balancing the songbook generation rate against spellbooks might be tricky, because although bards can still cast spells and other roles can play songs, each is not very likely to have that much use for the other set of books. Hardcoding different probabilities based on whether the character is a bard or not doesn’t seem very clean.
  • Possibly the bard should be able to discover songs by trial and error, although simple brute forcing is definitely not the way to do it. Maybe all spellbooks start identified.
  • The bard could need to practice the song by using the songbook in order to restore “song memory”. Song memory does not work quite like spell memory, it works essentially like direct success rate. There might be some mandatory delay between practices, meaning you can’t take an unlearned song and practice it up to 100% immediately. Or there could be a possible failure of practice, maybe a dexterity penalty (“Dumb move! You strain your fingers.”) to serve to prevent practice-spam. Playing a song would serve to
  • Songbooks do not eventually go blank, and can be used for practice indefinitely.
  • Or to keep it realistic with learning actual songs, you need to have the songbook on hand early on when you want to play it, but as you play it more and gain practice, you can eventually play the song without it anymore.
• The bard should possibly be able to sing some of their songs without requiring an instrument.

See also: Bard implementations.

Add a system for casting ritual spells: more powerful and more expensive spells which have some esoteric effects you can’t get otherwise. The main differences between ritual and normal spellcasting are that they consume valuable, hopefully non-renewable components, take a number of turns to cast instead of taking effect instantly, and may require you to be in or set up certain circumstances.

Various ritual spells that have been proposed:

• Ball spells which consume a gem as focus and create a ball of elemental power that hits surrounding squares but not you. (Long casting times would probably make rituals infeasible for combat though.)
• Temporarily increase your carry cap by a great amount. (Other new intrinsics as required.)
• Resurrect a corpse as a tame monster (necromancy).
• Grant temporary intrinsic life saving.
• Single controlled polymorph with a greatly increased duration.
• Summon a demon, demon lord, or demon prince. Requires 5 cursed candles and a marker (to draw the classic pentagram). If summoning a named demon lord, it’s either random or there’s some expensive way to control who shows up. The demon lord could be peaceful, but with current behavior this is useless. Possibly summoning them allows you to make a pact with them.
• Remove the graveyard status from a level (would need to be expensive, and perhaps involve the Book of the Dead, and multiple different headstones).
• Grow a tree. This consumes at least a piece of fruit. For anti-farming the tree should probably not produce fruit or bees when kicked.
• Create a portal between two levels of your choice (doesn’t work with the Amulet obviously, but otherwise works)
• Create an artifact (that is, you somehow imbue an item with properties it can’t normally get).
• Bless items. Consumes a blessed scroll of remove curse.
• Genocide a genocidable monster. Consumes a figurine of that monster plus other costly things.
• Reverse genocide a monster. The monster may or may not have to be normally reverse-genocidable. Consumes a figurine of that monster plus other moderately expensive things.
• Charge something. Requires a rare ingredient - perhaps a dilithium crystal.
• Summon tame elemental(s). Among other things, ingredients include: a potion of water, any beatitude (water); a rock (earth); lit candles, a lit oil lamp, or a lit potion of oil (fire); an amulet of magical breathing (air).
• Create a magic lamp. Needs an oil lamp (of course) and a figurine or mask of a djinni (or possibly a nearby live djinni).
• Make the current level non-teleport. Requires a scroll of teleportation and that the caster be standing on an anti-magic field at (?) either the start or the end of the ritual.
• Create a fountain. Requires a statue of a medium-sized or larger monster, which gets destroyed (by turning it into the centerpiece of the fountain). There may be potential for wishing abuse; perhaps the fountain should be flagged so that it can’t produce a wish-granting water demon.
• Turn a regular knife into an athame. Components include other bladed weapons with positive enchantments adding up to 20 or something; all of these charges will be drained to +0 in the creation of the athame. The resulting athame is +0, regardless of the charges on the component weapons or original knife.
• Create a tame golem or golems. Requires a large amount of total weight of objects made out of the golem’s material.
• Summon a coaligned angel or other minion of your deity as a pet.
• Create a tame wood nymph from a tree (only once per tree).

Ritual spells come in spellbooks like usual, but aren’t stored in your spell list. Instead, reading the spellbook prompts you if you want to begin its ritual and tells you the necessary ingredients and circumstances you need to satisfy as preconditions. If you meet all the conditions and answer yes, you initiate the ritual. (For simplicity, this should probably burn up / expend all the components instantly.) You cannot begin a ritual while in the process of casting another ritual; this should probably be implemented as a precondition.

Apart from the component cost, rituals act as a constant drain on your Pw until the ritual is complete. If something distracts you in the middle of the ritual, you can go take care of it and then resume the ritual as long as you have the Pw left to finish it. (You could also drink gain energy during the ritual.) The only way for a ritual to fail, possibly backfiring with bad effects, is for you to run out of Pw while it is incomplete.

In addition to its preconditions, each ritual also has some postconditions: common to all rituals is that you have been casting the ritual for at least some length of time, but there may be others, such as standing on the square where you began the ritual, or have another item, or kill a monster, or something. There may also be other conditions such as “moving off the space where the ritual started breaks and halts the ritual”.

Every time you stop casting a ritual (whether it succeeded or failed), it increments the spellbook’s spestudied field; the book will eventually disintegrate after casting it a certain number of times.

Items (perhaps only heavily randomized object classes, so NOT armor) can be inspected somehow, or else come pre-inspected, and your character is able to conclude that the item is one of a small set of possible things from that object class. The number of these possible things can depend on role, and the “fakes” are randomized every game. This approach is very similar to the one used in the roguelike Golden Krone Hotel.

Example: a character inspects a potion and confirms that it is either healing, acid, or sleeping. All potions with this appearance will provide the same three possibilities. It’s actually acid, but without other identification methods, or ruling out healing and sleeping, it can’t be discerned which of the three it is.

Has some problems with the interface; a character shouldn’t inspect everything and then have to type-name it. Perhaps this could be automated somehow.

Address startscumming by introducing a point buy system for starting characters: unrandomizing starting stats and inventory and letting the user spend points on stats and equipment however they like. (Note: dtsund’s class overhaul proposal also addresses unrandomization of starting inventory by simply removing all the random chances to get items, but it doesn’t involve point buy.)

Starting stats

• Any point buy for stats is likely to involve a tedious interface. Developers could get around this by making it options-only, perhaps in a way that allows the user to say “buy to get my Strength up to 10, and my Int up to 9, and randomly pick the rest”, but specifying it per-role could get annoying.
• It’s important to allow people who want to start and splat games rapid-fire to do so, and it would be preferable if new players didn’t have to learn the complexities of a new interface.
• The rc file must allow the user to specify starting stats per-role in this case, or specify that they want random stats.
• “Dump stats” like Cha, and Int and Wis for non-spellcasters, allow people to buff their important stats at the expense of unimportant stats, which may indicate some underlying balance issues with these stats or that the stats can have too wide of a starting range.

Starting inventory

• Even in a non-point-buy system, for starting inventory in cases like for Monk and Wizard where the player gets a random spellbook with equal weight among the possible choices, the player should be able to select which.
• Any point buy system for inventory should probably be options-only, since designing an interface to do so would be complicated.
• Naturally, items like magic markers and rings of polymorph control cost lots of points, whereas things like apples and oil lamps cost only a few.
• Some items should probably have maximums.
• This would come at the expense of players who actually want different nonrandom starting inventories and don’t want to have to edit their rc file every time.
• If the player’s options leave some or all of the available points free, the game will randomly buy items until there are no points left.
• Unspent points should probably convert into a certain amount of gold.
• Possibly the default items are expressed as a list which consumes most or all of the points and is sorted from highest priority to lowest, and ones the user specifies get moved to the beginning of the list, which will push the low-priority items into the range of not being able to be purchased.
• Certain items, like the knight’s lance and probably most armor, should not be purchasable, and the character always gets them.
• FIQ proposed a system in which you can specify one item, and the game will try to reroll your starting inventory many times until it gets that item. Since this is effectively built-in tool-assisted startscumming, it gets tracked as a conduct. However, making it a conduct could be self-defeating in that people who don’t want the game to show they broke the conduct will not use this system and continue to startscum.

A radically different system from how alchemy currently works, known as “1 + 1 = 2”: no matter how many potions are in the stacks being dipped, only one from each stack is consumed, and two alchemized potions are always produced.

• Intended as a balance fix for the player’s current ability to make stacks and stacks of full healing, gain ability, or gain level potions, and promote use of found potions instead of diluting them.
• Significantly, potions of holy water mostly work like they do now - the holy water does not mix with anything and is consumed, while the dipped item becomes blessed - but you can only dip a singular item into the holy water, including other potions. This loss of the ability to mass-produce holy water creates a significant balance change.
  • Or it could sometimes make two holy waters, but be biased against it, and allow both waters to become uncursed in the process.
  • Still unbalanced, since holy water can otherwise be mass produced through water prayers and blessed confused remove curse.
• Undiluted potions can be duplicated by dipping them in normal water, e.g. one potion of gain level + one water = 2 diluted potions of gain level.
  • Diluted potions may need to have weaker effects to compensate for this, or undiluted potions stronger effects.
  • Or potions in general should become rarer, and possibly generate diluted.

After killing certain type(s) of monsters (such as the monarch of a throne room), a timer may start that spawns an avenging posse of related monsters nearby.

A system termed “named non-artifact properties”. They are unique properties that never generate on more than one item per game, and confer some artifact-like qualities, but are not tied to a specific type of object, and can generate on multiple types of base item. This type of property cannot be wished for, even if properties can otherwise be wished for.

A couple examples:

• Any random ring could generate with a property that causes it to be named “Serpent’s Bite” and gives you a minor poison attack when hitting something with bare hands and the ring equipped.
• A few different types of fruit could generate with a property that causes it to be named “from Eris’s garden” and cause aggravate monster when carried.

Rather than having dragonhide items be generically “dragonhide”, let them each be a certain dragon color, which cannot be specified by wishing. This item does not confer the same extrinsic it would if it were body armor. Instead, when you are wearing dragon scales or mail and a dragonhide item of the same color in another slot, you gain a very powerful extrinsic which cannot be gained otherwise. E.g. cancellation immunity for gray dragon armor.

The idea is to discourage everyone continuing to wear gray or silver dragon scale mail: if you find or wish for dragonhide gear and get some other color, it may be attractive to wear dragon scale mail of that color instead in order to get the powerful extrinsic.

A system where your god grants you cool abilities, but only if you actively obey randomly generated edicts they put forth. Examples:

• “I declare the wearing of leather forbidden!” (persistent)
• “I declare Abipoppo the Shopkeeper must die!” (one-time)

If your god orders you to do something that would make you suffer alignment, anger, murder, or Luck penalties, you are not punished for that.

Conceieved as a new race, or an extension of the angelic race, but could also apply to Priests or Infidels.

A system for martial arts users in which moving tactically and positioning yourself translates to combat bonuses. Not a flanking system where you get better positioned with allies in place, but things like:

• Waiting a turn in place before throwing a punch makes it hit extra hard. (This synergizes with e.g. allowing a monster to approach you.)
• Jumping or teleporting around a monster before attacking it delivers an extra-powerful blow, with teleporting in particular being a coup de grace.
• Following up a hit with a kick makes it hit harder and/or knock the monster back.

The ideal balance to strike is that the game can be played without mastering this system, but if it is mastered the player becomes very effective in combat.

Dowsing rod, an item that you can engrave the name of an item on. Assuming the engraved name is a real object, it glows when one of those objects is on the same level as you, getting brighter the closer you are to it. (It doesn’t actually emit light on the map.)

Randomize the set of “critical” extrinsics and the base items that provide them in each game. I.e. instead of every game having a cloak of magic resistance, ring of free action, and amulet of reflection, the game could have a ring of reflection, a cloak of free action and an amulet of magic resistance.

A monster passive ability (possibly for shambling horrors or beholders) that unmaps its surrounding. This would be most useful when the monster also has something that incentivizes blinding yourself when near it, such as gaze attacks.

However, this can be negated by player note-taking of the map before the monster wipes it, so care should be taken not to make that worth doing.

A more in depth stealth mechanic. Involving hiding in containers, possibly on the ceiling if you can levitate, making monsters behave as if they can’t see you even in line of sight, creating illusions or using displacement to make diversions.

When you approach Mephisto and he is still peaceful, he does not demand tribute to pass like normal. Instead, he offers to buy your soul in exchange for powerful assistance on your quest to get the Amulet. If you agree, you are given amazing combat advantages (huge intrinsic damage boost, huge intrinsic AC boost, etc).

One of two bad things can happen as a result:

1. You have some chance, maybe 1/3, of failing to ascend when offering the Amulet to your god, as Mephisto claims your soul (the god still gets the Amulet but cannot raise you to immortality, so it’s a weird “win” that is not an ascension).
2. While ascending through Gehennom with the Amulet, he may reappear and try to take it and everything else for himself. All buffs he gave you are instantly removed and perhaps some debuffs are even applied. Possibly, defeating him in this circumstance could yield your soul back.

Alternatively he might appear on Astral, but that could be hard to explain flavor-wise. Or just create some test for if the player is in a sufficiently dire condition, and when they are he claims the player’s soul.

If you already have the Amulet the first time you meet Mephisto, he may not offer a bargain at all.

A status effect, probably caused by a potion, that removes all color from the game, but affecting more than just the map: color-based items cannot be differentiated, color-based monsters will not be distinguishable (e.g. a red naga and a black naga will just show up as “naga”, all dragons will just be “dragon”), and rays are reduced to some sort of generic ray effect (all dragon breath is just generic dragonbreath with no particular type, similar for all wand zaps).

Revamp Gehennom by making its main branch substantially shorter, a “hub” branch containing stairs or portals to a bunch of sub-branches containing demon lords’ lairs. Most of the lairs are optional, but at least some of them are required in order to enter the Sanctum. Each demon lord that you don’t kill, however, incurs a unique, harsh effect or debuff on you once you have the Amulet. Suggested ones include:

• The mysterious force, as it exists in vanilla.
• When you try to ascend the stairs, they vanish and several illusory copies of stairs appear across the level, along with one real one which you have to find.
• Walls extrude from existing walls around the hero in random directions, never entirely closing off, via a cellular automaton that looks for walls with a 3x2 area of walkable spaces in front of them, with the space directly in front a regular floor space - the effect of this given enough iterations turns the terrain around you into a maze.
• Generic damage over time, not severe but enough to provide a headwind. Or partial or total disabling of natural regeneration.
• Asmodeus: Some damaging cold effect that happens periodically, or your cold resistance is nullified and replaced with a vulnerability to cold effects.
• Baalzebub: Something to do with insects, either periodic summon insects from nowhere or stronger/more frequent insects
• Juiblex: You may randomly become ill, or have your regeneration dampened or something
• Geryon: Hordes of buffed q generate and rampage periodically.

Wielding Vorpal Blade in your offhand will never decapitate monsters; instead hits that would have decapitated will instead sever a limb, which can make the monster lose its weapon or permanently lose a claw attack.

When you enter Gehennom, the Sanctum is right there as one of the first couple of levels. But entering it transforms all the existing dungeon levels irreversibly into Gehennom levels, including demon lord lairs and the like. Everything in the Dungeons of Doom will be lost, and the player now has to work their way through the rest of Gehennom with the Amulet to enter the Planes.

Alternatively, and perhaps more straightforwardly, destroy the Dungeons of Doom when the player goes beneath the Valley of the Dead, and just have them enter the Planes directly from the Sanctum.

Add a new game mode in which everything goes wrong for everyone. Some examples: wands explode 50% of the time when used, all thrown/fired weapons can fly off randomly as if cursed, critical misses happen a lot, etc.

Make lycanthropy less random in when it triggers, allowing the player to know clearly when an episode is approaching, but make the effects when transformed more dangerous to the player. While transformed, the player is overtaken and controlled by an animalistic AI, giving no control to the player until they untransform.

Implement multiplayer as a system where each of the players is in a completely independent dungeon, generated with the same seed so that all levels and branches are created identical. There is a swapchest-like system for exchanging items between the games, without any limits on what can or can’t be swapped, other than unique items and that items can only be swapped within the same co-op game, not all existing games.

A certain type of chest (not a new object, just a specially flagged chest) that is magically protected; it cannot be opened, unlocked, be forced open, or destroyed until a certain monster on the level is either killed or leaves the level. Once it’s gone, the chest opens normally.

You can play a Vow of Poverty Monk, from D&D. This gives you insanely good bonuses and intrinsics, but you are prevented from having any worldly possessions on your journey (which is pretty much all items).

Items that fall into the abyss beneath Vlad’s Tower disappear from the game, and go into a swapchest-like system where they can be shared between different games. Players in other games may find those items showing up somewhere randomly in a demon lord’s lair when it gets generated.

When a creature is completely surrounded by enemies that have hands, or is completely surrounded by enemies that have hands except for squares it can’t safely move to (like walls, or water that it would fall into), every attack made against that creature is an automatic critical hit. This is to make it more difficult to just wade through a sea of monsters while ignoring most of their hits, and incentivize having pets to surround an enemy with.

Possibly, do a lesser version of this (critical hits only some of the time) when a creature is almost but not completely surrounded. Though it should probably require a certain amount of adjacent enemies or something; two opponents facing off in a straight, empty passageway shouldn’t count as “almost completely surrounded” by the walls.

Several issues have been pointed out with this system if implemented naively: getting “surrounded” by two monsters in a corridor or being surrounded instantly with summon nasties or a cursed scroll of create monster could pretty much spell instant death. The original idea was that being surrounded basically amounts to being held down so that all hits have maximum accuracy.

Revamping melee weapons:

1. Slashing (swords, axes) and blunt weapons (maces, flails) deal about the same base damage.
2. Swords’ main advantage is that they have a high chance of inflicting bleeding. Blunt weapons have a very low bleed chance but armor reduces their damage a lot less.
3. Bleeding steadily decreases the HP of the bleeding creature. It’s debated whether this should remove a few HP per turn (which would require increasing the HP of everything by a factor of 10 or so) or whether there should be a random chance (around 10%) of losing 1 HP on a given turn. (Possibly an algorithm that makes a monster lose 1 HP on one turn in every 10 - but the exact turn of HP loss isn’t predictable. For instance, if hash(monster id + (turns / 10)) % 10 == turns % 10, lose HP due to bleeding on this turn.)
4. Certain monsters are immune to bleeding, notably undead, golems, elementals, and others that don’t have vitals of any sort. These tend to be better killed with blunt weapons.
5. Bleeding can be fixed (or at least stanched) with bandages. Cloth items can be torn up to make bandages.

Revamped combat system:

1. All melee attacks randomly select a specific area of the body to hit, as well as regular misses, all out of the same pool.
2. Higher skill biases the pool “inward” on the body - some of the miss percentage will turn into outer limb hit percentage, some of the inner limb hit percentage will turn into a body hit percentage, etc. Head strikes are rare, but can inflict stunning as well as damage, although helms mitigate this somewhat.
3. Armor protects the area it covers, but its material or AC is a big factor in damage reduction: weak cloth armor takes full damage just like no armor, plate armor generally reduces damage completely except for rare armor-chink hits, etc.
4. Armor is strictly organized into four tiers of cloth, leather, mail and plate.
5. Positive weapon enchantment lowers the armor’s effective tier. Positive armor enchantment raises its effective tier. High armor enchantments are made substantially harder to come by.
6. Thrown daggers and knives are effectively useless against mail and plate armor, except for rare chink hits. Bow and arrow is useless against plate armor unless enchanted. Crossbow, however, is still useful against it. However, a successful shot deals a lot of damage.
7. On the monster side, many monsters (e.g. dragons) have effective full-body enchanted plate. Some monsters such as giants may also have powerful attacks that bypass armor.
8. Along with the limb-targeting system, it is also possible to break limbs. Broken limbs can be cured with prayer or most types of healing.

A much more fleshed out interaction system for sapient monsters. It is initiated by chatting, which opens up a menu offering four key verbs: Ask, Tell, Show, and Give.

Ask is used to gain information from a monster; this could be a whole bunch of things, from rumors to identification to information about the dungeon. Each type of monster you can ask things of has a limited knowledge base, and this knowledge base may contain some inaccurate information. Especially interesting is the possibility that you can ask someone for identification, and they tell you what they think it is - which could be right or wrong, but a good clue either way. You can also ask someone to join you, and pay them some gold to tame them for a certain amount of time.

Tell is currently a less developed part of this idea; the only thing suggested so far is that you can tell a creature about traps you’ve discovered, which will make those traps known to the creature. You can also use “tell calm” on your pets to make them refrain from attacking peacefuls.

Show lets you select any item from your inventory to show to the monster. This can be used for intimidation (e.g. showing a stack of iron skull caps to a goblin).

Give lets you give items to a monster, which in some cases, depending on the AI, lets you test the effects of items.

Note that a potential pitfall of such a system is that if it’s complex enough to do interesting things with, it is probably going to be hard to use without spoilers. And if it’s uncomplex enough, it runs the risk of most possible responses being “I don’t know/care about that”, which also makes it hard to use without spoilers. A middle ground between these is likely to require an enormous amount of work.

Monks who have passed through all the “Student of X” titles may go back and speak to the Grand Master to choose an elemental specialization and receive a power related to it. Stone gives a physical damage reduction; Air gives a random extra movement point here and there and a rare chance of dodging an attack. Water automatically counterattacks melee attacks. Fire boosts attacking power or gives extra attacks.

Traits or feats, selected when you create your character, and give you small buffs in the form of slight or situational effects. Buffs could include:

• Small increases to your maximum HP and Pw pools.

Things that can curse, steal, or change your name in-game.

If you fall asleep while having astral vision, you get astral projection. This consists of you spawning as some sort of incorporeal monster which can phase next to your body. Your body can’t move. Your projection can use your items like normal (consumables and charges are used up). If your projection dies, you return to your body and sleep out the remaining duration. If you wake up, your projection is destroyed and you return to your body normally; however, combat will not awaken you. If something else kills your body while you’re projected, you die and the game ends.

Artifact large box Pandora’s Box: it contains a ton of good loot, but opening it (or destroying it, or tipping it) alters several overarching gameplay mechanics that all make the game tougher.

Since it’s not as straight up beneficial of an artifact as most others, perhaps it shouldn’t count as a generated artifact for gifting/wishing purposes.

Monster speed system that tries to keep all the good qualities of 3.6.1’s while also not letting randomization make monsters super fast or super slow: add a 16 bit int to the monst struct, and every 12 turns set (speed % 12) of them to 1. Then on each turn, the monster gets (speed / 12) moves, plus 1 if the bit for that turn is 1. This 12-turn cycle would need to be phase shifted randomly per monster (probably using hashing based on monster ID) so that you can’t move-count based on the turn clock.

Research on an efficient algorithm to generate the series of 12 bits has found this, though it might be more entropy-efficient in the long run simply to generate all 4094 permutations of bits and randomly pick one with the correct number of bits whenever needed.

Premonition system: under various conditions (crystal balls, clairvoyance, dreaming while you sleep, the Oracle) you can receive a premonition of something that will appear later in your game (this could be almost anything: a monster, object, dungeon feature, special room, etc) which then has a very high chance of generating subsequently.

Equipment or artifact set bonuses, such that carrying or equipping all of them provides some bonus effect.

Spells can be “bound” together so that they can be cast simultaneously.

Silence auras that prevent both you and monsters spellcasting. Maybe also a directed silence spell, which silences an individual monster. While silenced, monsters can’t be chatted to, and nothing they do will make noise (possibly only if in a silence aura).

While under the effect of silence, the player’s stealth is elevated.

When potions break on the ground, they leave puddles of that potion. Pets can drink this puddle to get the effects. They also give effects (vapor effects, plus acid burning) to any monster standing in them, which is nice because it makes it harder for the player to stand in one place and fight a horde of enemies. Not defined what should happen if multiple potions mix in one spot - alchemize perhaps.

You have a lower chance of genociding monsters, wishing for items, and identifying canned food if you have never seen the monster or item in question.

Debilitating wound system that expands on wounded legs. Includes wounded arms and various types of disease and poison, all of which provide various debuffs. Quaffing any healing potion cures all of these at once on top of its usual HP healing.

Implement farming, in certain special rooms called greenhouses. Allows you to grow fruits, carrots, garlic, trees, etc.

If you have divine protection and become near death from a timed instadeath or low HP, some or all of your protection may automatically convert itself into a cure: “You suddenly feel the power of [deity] surround you! You feel limber/cured/much better/etc.” This should probably work for a narrow range of symptoms (probably not HP loss, possibly any major trouble), and the help delivered should be strictly worse than a prayer if possible (because having this trigger will not affect your prayer timeout).

It should also probably not work in Gehennom, and a key factor is that it should not be reliable, either. Possibly, also track which gods you got it from; protection from donating to crossaligned gods (especially Moloch) will trigger less often.

A slightly more extreme version of this idea is to make divine protection no longer grant AC at all.

New slot for belts:

• Belts themselves could be armor or tools, but probably armor. They mainly serve to hold items for quick access. It’s not defined whether they are intended to hold an indefinite number of items like any container, or a limited amount. The only problem with making them armor is that they would by default be enchantable for more AC, but belts should probably not be enchantable. If it makes more sense that several magical belts would hold charges, tools would be the appropriate class.
• Items carried in a belt weigh nothing and are mostly or totally protected from destruction, and using them doesn’t take the action it usually takes to get an item out of a bag.
• Types of belts could be scroll-holding, potion-holding, wand-holding, ammo-holding (with a possible “endless quiver” item or artifact), gem-holding (to get partial resistances from certain gems), chastity (providing immunity to foocubi seduction) or no special powers but some moderate AC.
• One randomized belt description could also provide protection against leprechaun theft.
• Randomized descriptions could include: cloth, leather, worn, studded, buckled, braided
• Tourists and Convicts also start off with garish swim trunks/striped slacks, which do the same things as Hawaiian shirts/striped shirts. The swim trunks also allow swimming. Both of these protect from instadeath when you sit on a cockatrice corpse.
• Belts of giant strength, elven grace, and troll toughness. These increase your Str/Dex/Con either to 25 or by +enchantment (if belts can even be enchanted, which isn’t currently defined.)
• Swordbelts/sheathes. These allow you to ready an additional weapon or give you an additional weapon slot.

More belt ideas here.