Splinter Twin + Barrenton Medic + Cathars' Crusade

Splinter Twin

Barrenton Medic

Cathars' Crusade

How it works

1. Activate Barrenton Medic by tapping it, creating a token copy of it with haste.
2. When the Barrenton Medic token enters the battlefield, Cathars' Crusade triggers, putting a +1/+1 counter on each creature you control.
3. Activate the nontoken Barrenton Medic's second ability by putting a -1/-1 counter on it, untapping it.
4. Repeat.

This delightful synergy transforms a humble protector into an endless army by turning the copy-making power of Splinter Twin loose on Barrenton Medic. While the newly minted token enters to trigger Cathars' Crusade—which permanently bulks up your board with fresh +1/+1 counters—the original Barrenton Medic relies on its own built-in untap ability, paying the cost with a -1/-1 counter that conveniently resets any damage counters. Because Cathars' Crusade immediately places a +1/+1 counter on the Medic as each new token arrives, those -1/-1 counters are perpetually neutralized, letting the Medic untap endlessly to fuel the twin-forged duplication loop.