I quite regularly dig out an Ancient favorite of mine called Dominus, the one good thing i snagged from Hotud before it went under.
The concept is simple enough, your the lord of a castle with questionable moral standing and you have to use creatures, magic, traps (all of which you can custom make) to fend off hordes of equally morally questionable fellows. Interrogate prisoners to find information on thier faction, capture thier leaders and make them retreat for good or send them to your dungeons and then experiment on them to create wierd super creatures.
Its an amazingly fun game and each playthrough can vary greatly.