Requires

Antler Skulkin must be on the battlefield. Ashnod's Altar must be on the battlefield. Phantom Flock must be on the battlefield. Phantom Flock does not have a -1/-1 counter on it. Mana needed:

Steps

1. Activate Antler Skulkin by paying , giving Phantom Flock persist until end of turn.
2. Activate Ashnod's Altar by sacrificing Phantom Flock, adding .
3. When Phantom Flock dies, its persist ability triggers, returning it to the battlefield from your graveyard with two +1/+1 counters on it due to its first ability.
4. Repeat.

Results