Retrofitter Foundry, Dross Scorpion, and Stridehangar Automaton

Prerequisites

• Retrofitter Foundry on the battlefield
• Dross Scorpion on the battlefield
• Stridehangar Automaton on the battlefield

Steps

1. Activate Retrofitter Foundry's fourth ability by tapping it and sacrificing a Thopter
2. When the Thopter dies, Dross Scorpion triggers, untapping Retrofitter Foundry
3. Resolve the Retrofitter Foundry ability, creating a 4/4 Construct and a 1/1 Thopter artifact creature token
4. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite creature tokens