Skullclamp + Pitiless Plunderer + Stridehangar Automaton + Heartless Summoning

Skullclamp

Pitiless Plunderer

Stridehangar Automaton

Heartless Summoning

How it works

1. Activate Skullclamp by paying 1, attaching it to a creature with toughness equal to 1.
2. The creature dies as a state-based action due to having 0 or less toughness, triggering Skullclamp and Pitiless Plunderer.
3. Resolve the Skullclamp trigger, causing you to draw two cards.
4. Resolve the Pitiless Plunderer trigger, creating a Treasure token and a 1/1 Thopter artifact creature token.
5. Activate the Treasure by tapping and sacrificing it, adding 1.
6. Repeat.