Ogre Enforcer

Oracle Text

Ogre Enforcer can't be destroyed by lethal damage unless lethal damage dealt by a single source is marked on it.

Card Rulings

10/4/2004 If its toughness falls to zero or less and it is undamaged, it will still be put into the graveyard.
10/4/2004 The check for nonlethal damage is done on a per-source basis. So each source’s damage is checked independently and it is not possible to team up sources (such as creatures) in order to kill it.