Specimen Collector + Everquill Phoenix + Ashnod's Altar + Rukarumel, Biologist

Specimen Collector

Everquill Phoenix

Ashnod's Altar

Rukarumel, Biologist

How it works

1. Cast Everquill Phoenix for its mutate cost by paying 3, putting it under or over a non-Human creature you control.
2. Everquill Phoenix triggers, creating a Feather artifact token.
3. Activate Ashnod's Altar by sacrificing Specimen Collector, adding CC.
4. When Specimen Collector dies, its second ability triggers, creating a copy of the Feather token.
5. Activate a Feather by paying 1 and sacrificing it, returning Specimen Collector from your graveyard to the battlefield.
6. When Specimen Collector enters the battlefield, its first ability triggers, creating a 1/1 Squirrel and a 0/3 Crab creature token.
7. Repeat from step 3.