Curiosity
Innistrad — uncommon
Enchantment — Aura
Curiosity rulings:
2023-09-01: Curiosity doesn't trigger if the enchanted creature deals damage to a planeswalker or to a battle.
2023-09-01: You draw one card each time the enchanted creature deals damage to an opponent, no matter how much damage it deals.
2023-09-01: If you control Curiosity and it's enchanting an opponent's creature, you won't draw a card when that creature deals damage to you. The creature has to deal damage to one of your opponents for the ability to trigger.
2011-09-22: "You" refers to the controller of Curiosity, which may be different from the controller of the enchanted creature. "An opponent" refers to an opponent of Curiosity's controller.
2011-09-22: Any damage dealt by the enchanted creature to an opponent will cause Curiosity to trigger, not just combat damage.