Enchant creature
Enchanted creature gets +2/-1.
When enchanted creature dies, choose a creature at random this Aura can enchant. Return this card to the battlefield attached to that creature.
You can't return this card to the battlefield onto something it can't enchant. For example, you can't place this card on a permanent with protection from red.
When this card returns to the battlefield, it is put onto the battlefield on the creature without targeting it, so it can be placed on a creature with Shroud.