Grim Poppet + Nest of Scarabs + Synth Infiltrator

Grim Poppet

Nest of Scarabs

Synth Infiltrator

How it works

1. Activate Grim Poppet by removing a -1/-1 counter from it, putting a -1/-1 counter on Synth Infiltrator.
2. Nest of Scarabs triggers, creating a creature token.
3. Activate Synth Infiltrator by removing a -1/-1 counter from it, putting a -1/-1 counter on Grim Poppet.
4. Nest of Scarabs triggers, creating a creature token.
5. Repeat.