Gain control of all creatures until end of turnInfinite creature tokensInfinite creature ETBInfinite mana creatures you control can produceInfinite untap of creatures you control
How it works
Activate Marrow-Gnawer by tapping it and sacrificing another Rat, creating at least one 1/1 Rat creature token.
When the Rat enters the battlefield as a Pirate due to Xenograft, Coercive Recruiter triggers, untapping Marrow-Gnawer.
Repeat.
If you control at least two other Rats, this combo creates infinite additional Coercive Recruiter triggers, which can be used to untap any creature(s) infinitely and/or to gain control of any number of creature(s) until end of turn.
This ingenious loop turns Marrow-Gnawer into a relentless engine by leveraging Xenograft to reclassify every creature you control as a Rat—and, crucially, a Pirate. With that foundational type-shifting in place, sacrificing a creature to Marrow-Gnawer’s tap ability produces new Rat tokens whose very arrival triggers Coercive Recruiter. Because those tokens instantly count as Pirates, Coercive Recruiter's entry ability targets and untaps Marrow-Gnawer, allowing you to repeat the sacrifice indefinitely and flood the board with an endless horde of tokens.