Szarel, Genesis Shepherd + Puppeteer Clique + Altar of Dementia

Szarel, Genesis Shepherd

Puppeteer Clique

Altar of Dementia

How it works

1. Activate Altar of Dementia by sacrificing Puppeteer Clique.
2. When Puppeteer Clique dies, its persist ability and Szarel trigger.
3. Resolve the persist trigger, returning Puppeteer Clique from your graveyard to the battlefield with a -1/-1 counter on it.
4. When Puppeteer Clique enters, it triggers, putting a creature card from an opponent's graveyard onto the battlefield under your control.
5. Resolve the Szarel trigger, putting a number of +1/+1 counters on another creature you control.
6. Resolve the Altar of Dementia ability from step 1.
7. Activate Altar of Dementia by sacrificing the creature returned in step 4.
8. When the creature dies, Szarel triggers, putting a number of +1/+1 counters on Puppeteer Clique.
9. Resolve the Altar of Dementia ability.
10. Repeat.

This loop centers around Puppeteer Clique repeatedly entering and leaving the battlefield, weaponized by Altar of Dementia to endlessly mill your opponents' libraries while generating infinite death and sacrifice triggers. Because Puppeteer Clique has persist, it can return from the graveyard to the battlefield, but it normally acquires a -1/+1 counter that would shut down the recursion. This is where Szarel, Genesis Shepherd shines: its static ability allows you to play lands from your graveyard, while its triggered ability uses the permanent sacrifices to pump up your creatures, specifically placing +1/+1 counters on Puppeteer Clique to cancel out its -1/-1 counters and keep the loop going indefinitely.