How it works
Prerequisites
- You control a non-Human creature.
- You have a creature card exiled with Semblance Anvil.
Steps
- 1Cast Cubwarden for its mutate cost by paying , targeting a non-Human creature you control.
- 2The Cubwarden mutated creature triggers, creating two 1/1 Cat creature tokens.
- 3Activate Phyrexian Altar by sacrificing the Cubwarden mutated creature, adding .
- 4When the Cubwarden mutated creature dies, Enduring Renewal triggers, returning Cubwarden and any cards merged with it from your graveyard to your hand.
- 5Activate Phyrexian Altar by sacrificing a Cat token, adding .
- 6Repeat.
Commander brackets
In which brackets is this combo allowed, per Spellbook's Exhibition tier?