Putrid Goblin + First Day of Class + Altar of Dementia

Putrid Goblin

First Day of Class

Altar of Dementia

How it works

1. Cast First Day of Class by paying 1, causing all creatures that enter the battlefield under your control this turn to get an additional +1/+1 counter put on it.
2. Activate Altar of Dementia by sacrificing Putrid Goblin.
3. Putrid Goblin's persist ability triggers, returning itself from your graveyard to the battlefield with a -1/-1 counter on it.
4. Putrid Goblin enters the battlefield, triggering First Day of Class, putting a +1/+1 counter on Putrid Goblin.
5. Resolve the Altar of Dementia ability from step 2, causing target player to mill cards equal to Putrid Goblin's power.
6. Repeat from step 2.