Demonic Sapphire

A guiding stone that evokes only strong selfish desires. Simulacrums of a certain Demon warrior were mass produced abhorrent technology. They have the same appearance, personality and ability...but no memory. If they were to be unleashed without being given a purpose, they would eventually begin killing each other, and begin thinking, "Who are you?", "Is one of us the real one?", "Am I a fake?"... And in the end, this stone might lend its power to the sole survivor.