Promised Kannushi + Arcane Adaptation + Ashnod's Altar + Gemstone Array

Promised Kannushi

Arcane Adaptation

Ashnod's Altar

Gemstone Array

How it works

1. Activate Ashnod's Altar by sacrificing Promised Kannushi, adding CC.
2. When Promised Kannushi dies, its soulshift ability triggers, returning itself from your graveyard to your hand.
3. Activate Gemstone Array's first ability by paying 2, putting a charge counter on it.
4. Activate Gemstone Array's second ability by removing a charge counter from it, adding .
5. Cast Promised Kannushi by paying .
6. Repeat.