Could it be Werewolves Of Londen -
http://www.mobygames.com/game/werewolves-of-london
You have to kill relatives of those that gave you the werewolf curse. And judging from the screenshots, there seems to be day cycles (human) and night cycles (werewolf)
http://www.mobygames.com/game/werewolves-o...don/screenshots
