Sigarda's Summons + Bishop of Wings + Cathars' Crusade + Altar of Dementia

Prerequisites

• You control an additional Angel.

Steps

1. 1Activate Altar of Dementia by sacrificing an Angel.
2. 2Bishop of Wings triggers, creating a 1/1 Spirit creature token.
3. 3The Spirit enters the battlefield, triggering Cathars' Crusade, putting a +1/+1 counter on each creature you control.
4. 4The Spirit token becomes a 4/4 Spirit Angel due to having a +1/+1 counter on it.
5. 5Resolve Altar of Dementia's ability, causing target player to mill cards equal to the Angel's power.
6. 6Activate Altar of Dementia by sacrificing the Spirit token.
7. 7Repeat from step 2.

Effects

• Infinite +1/+1 counters on creatures you control
• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers
• Infinite mill
• Infinite self-mill