Cayth, Famed Mechanist + Yahenni, Undying Partisan

WUBR identity

Commander legal

The 2 combo pieces

What must be in place

The persist creature does not have a -1/-1 counter on it.

How to execute it

  1. Activate Yahenni by sacrificing the persist creature.
  2. When the persist creature dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
  3. When the persist creature enters the battlefield, its fabricate ability triggers, putting a +1/+1 counter on it.
  4. Resolve the Yahenni ability, giving it indestructible until end of turn.
  5. Repeat.

What the combo produces