Phantasmal Assassin (3.5e Spell)

You stick the image of an angel of perfect light in the target's head, and it manipulates them into walking off the cliff.

If the target fails their Will save, you create a Sentient Illusion with the personality and goals you desire in their mind. It is a Commoner with a character level equal to your caster level, and no feats or skills. The Sentient Illusion is not a Stationary Illusion, and can swap bodies as often as it likes.

In general, it can be assumed that you give the Sentient Illusion a goal of "doing whatever the caster says".