Szarel, Genesis Shepherd + Cauldron of Souls + Clock of Omens + Krark-Clan Grunt

Szarel, Genesis Shepherd

Cauldron of Souls

Clock of Omens

Krark-Clan Grunt

How it works

1. Activate Cauldron of Souls by tapping it, giving two nontoken artifact creatures persist until end of turn.
2. Activate Clock of Omens by tapping the nontoken artifact creatures, untapping Cauldron of Souls.
3. Activate Krark-Clan Grunt by sacrificing one of the nontoken artifact creatures that doesn't have a -1/-1 counter on it.
4. When the creature dies, its persist ability and Szarel triggers.
5. Resolve the persist trigger, returning the creature from your graveyard to the battlefield.
6. Resolve the Szarel trigger, putting a number of +1/+1 counters on the other artifact creature.
7. Resolve the Krark-Clan Grunt ability.
8. Repeat from step 3 once, instead sacrificing the creature who had counters placed on it in step 6.
9. Repeat from step 1.

This intricate engine transforms ordinary artifacts into an infinite loop of recycling and growth, legal in formats like commander and legacy. By tapping Cauldron of Souls, you grant two artifact creatures persist, allowing them to dodge death the first time they perish by returning with a -1/-1 counter. Clock of Omens harnesses those very creatures to endlessly untap the Cauldron, while Krark-Clan Grunt stands ready to feed them into the graveyard as needed. Whenever a permanent meets its end here, Szarel, Genesis Shepherd notices and piles massive +1/+1 counters onto the survivors—canceling out those pesky -1/-1 counters and permanently pumping your team while allowing you to replay lands straight from the graveyard for even more value.