[Bug Fix] Revert 2df7d19

This change breaks lich-type spells as seen in #4098. Per comment on original change, also don't see where Runes come into play.

zone/attack.cpp

@@ -4103,7 +4103,7 @@ void Mob::CommonDamage(Mob* attacker, int64 &damage, const uint16 spell_id, cons
 		}
 
 		if (IsClient()) {
-			CommonBreakInvisible();
+			//CommonBreakInvisible();
 		}
 
 		if (attacker && attacker->IsClient() && attacker->CastToClient()->sneaking) {