Add more monsters, probably additional types of eyes, which have various area-of-effect “auras”: not attacks, but things which inflict both good and bad statuses on everything around them. Effects could range from slowing down, to conflict, to confusion, and various other things.
Breaking a wand of healing or extra healing should heal monsters in the 3x3 area around you.
Angering peaceful monsters by casting an innocuous spell like light is very annoying, so split the spell up into a “light area” spell, which does not damage anything unless it’s a highly light-sensitive monster like a gremlin, and a “light blast” or “flash” attack spell, which may or may not light the area permanently and is designed to blind monsters.
An Alchemist role, revolving around potions and alchemy, and likely requiring overhauls of several systems.
The invoke effect of the Philosopher’s Stone is heavily debated.
A really great Alchemist implementation would probably involve a full alchemy overhaul which adds herbs and fungi, harvesting ingredients from corpses, cooking, and interesting ways to combine everything. The challenge with making this is how to make it useful for other roles and not just the alchemist, and at the same time not overcomplicating the game with the new additions.
A monster spell which does high area of effect damage, but clearly indicates what that area of effect will be a turn or two before it goes off, so the player can possibly get to safety.
A SpliceHack spell to make splatters of blood have a use case. It causes blood splatters in a area scaling from 3x3 to 7x7 around the caster (depending on skill) explode, dealing physical damage to things caught in the explosions. Blood splatters on the floor are cleared, and new blood being caused by something dying might be suppressed if it becomes too easy to repeatedly cast this for lots of explosions.
As proposed, this would be a level 5 attack or matter spell.
A silence spell for either players or monsters or both. Not specified whether it would be area-of-effect or targeted at specific creatures. The main function of silence effects would be to prevent spellcasting. Not specified whether this would also affect reading scrolls (though probably not since you can “cogitate” the formula on scrolls if polymorphed into a speechless form).
However, this may require defining certain existing spells as not requiring speech, because it does not seem entirely fair to take away all of someone’s escape or healing spells with fairly low level magic.
Assuming a player fear system is implemented, Nazgul should passively cause fear in the player as an area of effect (or a gaze if this is too hard to implement).
The sleep spell has an advanced form, castable only at Expert, which creates area of effect sleep like a magic flute does.
If polymorphed into a sufficiently strong monster, you can force-fight down or kick the ground to cause a shockwave that hits all immediately adjacent ground-bound monsters.
Invoking the Tsurugi of Muramasa causes a fear effect similar to reading scare monsters and gives a temporary effect equivalent to increase damage (possibly only on hits made with the Tsurugi, possibly with any weapon).
It was also pointed out that triggering a temporary effect by invoking could get tedious. Another suggestion was to give it some sort of passive fear-causing effect when wielded (in addition to the one-time scare when invoking it).
Archons’ light radius should be a passive aura area-of-effect attack that causes strong light effects: potentially blinding normal monsters, hurting gremlins and undead, petrifying trolls, and so on.
Remove sleep as a ray. Sleep wands (and monsters with sleep breath like orange dragons and Nazgul) instead shoot a beam of sleep. The sleep spell either also shoots a beam of sleep or causes sleep in an area of effect. Sleep could also possibly be a cone, spreading out in the direction it’s shot in, but cone spells remain unimplemented.
Fire and frost horns, rather than shooting a bouncable ray of fire or cold, cause a powerful area fire or frost effect centered on you. The intensity diminishes the farther away from you it gets, but it hits every single creature in its fairly large radius (except you).
This effect could also freeze water and lava or evaporate pools in the radius of effect as well.
Spells whose main purpose is to buff allies within an area of effect. (They will give the player the buff too, but the buffs won’t be a huge improvement for a single creature. So you get more out of the effect the more allies you can affect with it, and it’s best used when you have allies around).
Ring spells, level 7 (or even 8) attack spells, which cast a ring of some elemental power emanating from your square that does not hit your square itself. The radius is 1 if Unskilled or Basic and 2 if Skilled or Expert.
Potions of acid have a splash radius effect when broken (could probably be implemented as an acid explosion).
When a light explodes, all monsters adjacent to it are affected equally.
Artifact weapon that creates a shockwave upon hitting a monster, dealing minimal damage to other monsters behind it.
Various forms of AoE monster-debuff candles. Charm them, anti-undead, etcetera.
Make potions of oil more common, so that the player has more area-of-effect combat options (for throwing firebomb potions of oil). Possibly allow hardware stores to stock them.
Polymorph potions affect all monsters adjacent to where they shatter.
Make more potions effective for throwing at monsters, first by making the vapor effects hit more than just whoever they were thrown at (i.e. splash effects), and then by making more potions have a vapor effect that affects monsters.
