In both
Nethack and
Slash'Em, it is possible for your character to
hallucinate. This is most commonly caused by drinking a
potion of
hallucination or an exploding black light (which causes hallucination
for a somewhat shorter period), but there are other
obscure causes,
such as applying a cursed
unicorn horn.
The main effect of hallucination is that the appearance of all
monsters and items changes every move, making it impossible to
determine which monsters are hostile. In vanilla Nethack, you can
see the true forms of objects on the ground or in your inventory,
but in Slash'Em you cannot. There are also some other minor effects -
for example, in Slash'Em some shopkeeper services will not work
properly and you will be unable to use techniques which require
concentration - and many YAFMs are associated with hallucination.
Hallucination caused by a black light only lasts for about 100
turns, so if you can't cure it, you can just wait for it to wear
off. Hallucination caused by a potion of hallucination lasts for much
longer, and you will get hungry if you try to wait all that time.
In Nethack, you can keep going if you are careful. Leave your pet
behind so you don't kill it, stay away from Minetown or anywhere
else with large numbers of peaceful monsters, and watch out for
hallucinogen-distorted floating eyes. In Slash'Em, however,
hallucination is a crippling disability, as you cannot recognise
anything. It's best not to drink potions that might be hallucination
unless you have a means of curing yourself.
The commonest method of curing hallucination is to apply a unicorn
horn. You can also quaff a potion of extra healing, full healing or
sickness (if you don't mind the loss of stats and hit points).
Wielding Grayswandir conveys hallucination resistance. There is a
small chance that prayer will cure hallucination.