Viscera Seer + Heartmender + Thran Vigil

Viscera Seer

Heartmender

Thran Vigil

How it works

1. Activate Viscera Seer by sacrificing Heartmender.
2. When Heartmender dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. Thran Vigil triggers, putting a +1/+1 counter on Heartmender.
4. Resolve the Viscera Seer ability.
5. Repeat.

This brilliant looping engine sets up a perpetual motion machine in your graveyard and on the battlefield using Heartmender as the central pivot. When you sacrifice Heartmender to Viscera Seer, its persist ability brings it right back with a -1/-1 counter, which instantly triggers Thran Vigil as it leaves the graveyard. Thran Vigil patches up the damage by dropping a +1/+1 counter onto the returning creature, where state-based actions immediately cause the +1/+1 and -1/-1 counters to annihilate each other. Because Heartmender is now clean of counters once again, you can feed it right back to Viscera Seer to repeat the cycle indefinitely, generating an endless stream of sacrifice triggers, scry depth, and creature movement.