[fph]

Nethack is one of the wildest. So many hardcoded edge cases and wild interactions.

From the wiki: "Food rations have a 1/7 chance of being rotten when eaten if they are uncursed and older than 30 turns, or else are blessed and older than 50 turns, while cursed food rations are always rotten. Food rations can be thrown to tame domestic canines and felines and pacify domestic equines. "

[n4r9]

The game takes on a new level when you find you can build an army of big cats, or gallivant about with a lance on a warhorse (P.S. nevertheless this is still newbie stuff. I never got very far after many hours of attempts...).

[somat]

It is probably just me But I find it especially fun to play with a copy of the source code open, using it as a cryptic but thorough guide.