Dross Scorpion + Detective's Satchel + Carrion Feeder

Dross Scorpion

Detective's Satchel

Carrion Feeder

How it works

1. Activate Detective's Satchel by tapping it, creating a 1/1 Thopter artifact creature token.
2. Activate Carrion Feeder by sacrificing the Thopter.
3. When the Thopter dies, Dross Scorpion triggers, untapping Detective's Satchel.
4. Resolve the Carrion Feeder ability.
5. Repeat.

This cunning loop uses Detective's Satchel as a factory, tapping it to produce a Thopter token once you've met its sacrifice condition. Carrion Feeder steps in to sacrifice that Thopter, growing larger with a +1/+1 counter while feeding the engine. Because that Thopter is an artifact creature, its demise immediately triggers Dross Scorpion, whose passive mastery untaps Detective's Satchel so the cycle can begin anew.