Perhaps the game could allow you to eat some of the remains of what you kill. This could give you nourishment or make you sick (i.e. depending on what your race/type/alignment). If you look at the Rogue game, if you ate some of a monster you killed you could also gain some of the attributes of that monster.

For instance, if a monster that could poison you in an attack, then perhaps eating some of that monster might confer some resistance to the poison attack of that monster in the future.

This would incur some overhead in the program. It would have to determine if enough of the monster remained after an attack to be available for eating. It should also take into account the type of attack on the monster to determine the remains. Killing something with arrows would leave a lot of intact remains. Killing something by exploding a barrel would probably not.