Ring or amulet that causes your spellcasting to draw on HP instead of Pw, possibly only when your Pw is zero, or possibly not requiring a ring. Each point of HP is worth 2 Pw points. If cursed, doubles spell Pw costs. If blessed, energy regeneration will regenerate HP until full before regenerating Pw. Casting from HP too much may decrease your HP maximum. If implemented as an artifact, possibly flavor it as an evil counterpart of the Eye of the Aethiopica.

Note that a couple variants have implemented this as a “ring of blood magic” or similar items.

If you have teleport control, quantum mechanics’ attacks toggle your speed instead of giving you a free controlled teleport.

A Minetown (or some other town) minigame based around classic survival/area defense games:

• Takes place in a smaller-than-Minetown square walled area in a large open part of the mines.
• Orcs, with a very high spawn rate and an increasing difficulty modifier, appear around the edges of the map.
• The walls will block the weakest and the unequipped from entering the town proper, but it won’t be good once orcs start showing up with pickaxes and ladders.
• To prevent the orcs from building up a horde, there are some weaker points in the walls, maybe a gate they can try to bash down or an unrepaired breach. These must be defended with manpower and all the traps you can think to lay.
• Orcs grudge everything inside the town, and vice versa; meanwhile, nothing in the town is hostile to you.
• Shopkeepers sell you items from their limited inventory at very cheap prices.
• There are watchmen who can hold back an incursion, but they’ll eventually fail if the player isn’t able to get there in time.

If the player sits on a throne after being crowned, even in non-royal polyforms, they get the royalty message.

Nazgul cannot be killed “incorrectly” (unclear on what this needs to be, perhaps stabbing them with a barrow-wight’s knife, or being female). If you happen to kill one incorrectly, it will be killed without giving experience and its inventory will be deleted (minus unique items). The Nazgul born counter then ticks down by one, so it can be spawned again elsewhere by the normal mechanism.

You occasionally get an alignment bonus if your alignment record is negative and you are Weak, because you are doing hunger penance. (Possibly only works for lawfuls, since chaotic gods are unlikely to approve of weakness.)

Rust traps’ item rusting is delayed. You can use a towel to prevent a wetted item from rusting.

Charging a potion of fruit juice turns it into a potion of see invisible. Dipping fruit juice into confusion turns it into a potion of booze.

A windowport that allows you to configure local sound files to play when the game produces certain messages.

Pacifist option, which suppresses the normal bump-to-attack mechanic. (You can still attack with the F command.)

Quantum mechanics’ hits toggle your speed instead of teleporting you if you have teleport control. (You already know your position, so your velocity must become uncertain.)

Change up and add new failure effects of spellbook reading:

• Any failure confuses you instead of paralyzing.
• The level 5+ confusion effect seems quite tame in comparison to the other effects, so replace it with paralysis.
• New effect: book tries to eat you
• New effect: level drain
• Spell enters your head automatically, but erases your knowledge of one/all of your other spells. (This could be quite annoying and may be better off as an Evil Patch Idea.)
• New effect (possible in combination with other effects, and for any book): book curses

Books no longer have a 1/3 chance of disintegrating when failing to read them; instead, a cursed book will always disintegrate.

New msgtype intended to be even stronger than msgtype:stop, perhaps called msgtype:paranoid. Requires the user to type “yes” before continuing.

Note: A patch has since been created for msgtype:alert, which forces you to hit tab before continuing.