Putrid Goblin + First Day of Class + Goblin Trashmaster

Prerequisites

• There's an artifact on the battlefield.

Steps

1. 1Cast First Day of Class by paying
2. 2Activate Goblin Trashmaster by sacrificing Putrid Goblin
3. 3When Putrid Goblin dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
4. 4When Putrid Goblin enters, First Day of Class triggers, putting a +1/+1 counter on Putrid Goblin.
5. 5Resolve the Goblin Trashmaster ability.
6. 6Repeat from step 2

Effects

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers