What video games let you possess people on

some RTS games have some kind of possession move. In Warcraft 3, the Undead faction's Banshee's can take over enemy units permanently. In Dungeon Keeper 2 - and possibly Dungeon Keeper but I haven't played that game - you can cast a spell to possess your minions that live in your dungeon, making the minion more powerful, especially with a human intelligence behind it instead of an artificial one.