Moritte of the Frost, Staff of Eden, Vault's Key, and Kappa Cannoneer

Prerequisites

• Moritte of the Frost in hand or in the command zone
• Staff of Eden, Vault's Key on the battlefield
• Kappa Cannoneer on the battlefield
• plus enough mana to pay for commander tax, if applicable available

Steps

1. Cast Moritte of the Frost from your hand or from the command zone by paying plus commander tax, if applicable, choosing to have it enter the battlefield as a copy of Staff of Eden
2. Put Moritte of the Frost into your graveyard due to the legend rule
3. Morrite of the Frost's enters-the-battlefield ability and Kappa Cannoneer trigger
4. Resolve the Kappa Cannoneer trigger, putting a +1/+1 counter on it and causing it to be unblockable this turn
5. Resolve the Moritte of the Frost trigger, returning Moritte of the Frost from your graveyard to the battlefield as a copy of Staff of Eden
6. Repeat from step 2

Results

• Infinite +1/+1 counters on Kappa Cannoneer