Activate Krenko by tapping it, creating at least two 1/1 Goblin creature tokens.
Activate Goblin Trashmaster by sacrificing a Goblin token, targeting any artifact.
When the Goblin dies, Krenko triggers, untapping itself.
Holding priority, repeat from step 1.
Resolve all Goblin Trashmaster abilities, destroying the targeted artifact(s).
You may also repeat this loop whenever an artifact enters the battlefield.

Destroy all artifacts that enter the battlefield under an opponent's control

Destroy all artifacts opponents control

Infinite creature tokens

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Infinite creature sacrifice triggers

Lock

Krenko, Mob Boss

Thornbite Staff

Goblin Trashmaster

Activate Goblin Trashmaster by sacrificing Putrid Goblin.
When Putrid Goblin dies, its persist ability triggers, returning it from your graveyard to the battlefield without a -1/-1 counter on it due to Metallic Mimic.
Resolve the Goblin Trashmaster ability.
Repeat.

Putrid Goblin

Metallic Mimic

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

First Day of Class

Activate Goblin Trashmaster by sacrificing a creature with mana value 1 or less.
When the creature dies, Mortuary triggers, putting the creature from your graveyard onto the top of your library.
Resolve the Goblin Trashmaster ability.
Cast the creature from the top of your library by paying 1 life.
Bontu's Monument triggers, causing you to gain 1 life
Repeat.

Combos with "Goblin Trashmaster"