When Meathook Massacre II enters, each player sacrifices X creatures of their choice.
Whenever a creature you control
diesIs put into a graveyard from the battlefield. (CR 700.4), you may pay 3 life. If you do, return that card under your control with a finality
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) on it.
Whenever a creature an opponent controls
diesIs put into a graveyard from the battlefield. (CR 700.4), they may pay 3 life. If they don't, return that card under your control with a finality
counterTo counter a spell or ability is to cancel it: remove it from the stack without resolving it. A counter on an object or player is instead a marker that changes characteristics or interacts with rules or abilities; for example, a +1/+1 counter modifies a creature’s power and toughness. (CR 701.6; 122.1) on it.