THIS IS A SPOILER! I wrote it based on 0.7.2's spells1.c, in the function project_p.
DO NOT READ ON if you would rather figure this out yourself!
The way chaos elemental attacks work is this:
If the player resists chaos, initial damage is reduced by a factor of 0 to 200%.
If the player does not resist confusion, the player is confused for an additional 10-30 turns. (This is cumulative.)
If the player does not resist chaos, the player hallucinates for an additional 0-10 turns. (This is cumulative.)
If the player does not resist both nether and chaos, and he DOES have Hold Life, he'll have a 75% chance of holding onto his EXP (with the other 25% chance of losing 500+[EXP/1000]*monster's desired drain life amount). If he doesn't have Hold Life, he loses 5000+[EXP/100]*monster's desired drain life amount.
After all that has been computed and applied, the HP damage is then taken from the player.
SO: If you resist chaos and nether, you'll be all set! Otherwise you'd better resist confusion, and have Hold Life.
Ouch, pretty nasty!
SPOILER: Chaos effects
SPOILER: Chaos effects
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