Sleep with the Fishes
Enchantment — Aura
Enchant creature
When this Aura enters, tap enchanted creature and you create a 1/1 blue Fish creature token with "This token can't be blocked."
Enchanted creature doesn't untap during its controller's untap step.
Randy Gallegos
Rulings
If the creature targeted by Sleep with the Fishes isn't a legal target at the time it would resolve, Sleep with the Fishes is put into its owner's graveyard from the stack. It's not put onto the battlefield and then put into their graveyard. Notably, this means that its controller will not create a Fish token.
(wotc • 2022-04-29)
Rulings
If the creature targeted by Sleep with the Fishes isn't a legal target at the time it would resolve, Sleep with the Fishes is put into its owner's graveyard from the stack. It's not put onto the battlefield and then put into their graveyard. Notably, this means that its controller will not create a Fish token.
(wotc • 2022-04-29)