Q u o t e: well on diablo 2 single player the monsters didnt respawn after you killed them. kinda hoping they respawn on single player.
In Diablo 2, after you log out when you log in back, every mobs respawn. Both Single Player, LAN and Battle.net (closed and opened) works that way. This is how I grind more level when I feel myself too low (yes, I STILL play D2 ;-)
In Diablo 1, mobs never respawn after killing them, even after logging out and in. In order to kill them back, you have to start a new game, but it is possible to start a new game using your already existing character though.
A clear conscience is usually the sign of a bad memory.