Antler Skulkin + Ashnod's Altar + Arcbound Prototype

Antler Skulkin

Ashnod's Altar

Arcbound Prototype

How it works

1. Activate Antler Skulkin by paying 2, giving Arcbound Prototype persist until end of turn.
2. Activate Ashnod's Altar by sacrificing Arcbound Prototype, adding CC.
3. When Arcbound Prototype dies, its modular and persist abilities trigger.
4. Resolve the modular trigger, putting all +1/+1 counters on Arcbound Prototype onto another artifact creature you control.
5. Resolve the persist trigger, returning Arcbound Prototype from your graveyard to the battlefield with one +1/+1 counter on it due to its modular ability.
6. Repeat.