Time Sieve + Encroaching Mycosynth + Bishop of Wings + Xenograft

Time Sieve

Encroaching Mycosynth

Bishop of Wings

Xenograft

How it works

1. Activate Time Sieve by tapping it and sacrificing five other creatures.
2. When the creatures die as Angels due to Xenograft, Bishop of Wings' second ability triggers five times.
3. Resolve the first trigger, causing you to create a 1/1 Spirit creature token.
4. When the Spirit enters the battlefield as an Angel due to Xenograft, Bishop of Wings' first ability triggers, causing you to gain 4 life.
5. Repeat from step 3 for each remaining trigger.
6. Resolve the Time Sieve ability from step 1, causing you to take an extra turn after this one.
7. Repeat each turn.

By casting Xenograft and naming "Angel," you radically rewrite the identity of every creature you own, allowing Encroaching Mycosynth to step in and turn those same nonland permanents into artifacts so they can be fed directly to Time Sieve's sacrifice cost. Every time you feed five of these creatures to Time Sieve for an extra turn, Bishop of Wings springs into action by triggering its death ability to replace them with Spirit tokens. Because Xenograft and Encroaching Mycosynth ensure those entering tokens arrive simultaneously as Angels and artifacts, Bishop of Wings's entry ability floods you with life while providing the exact fodder needed to immediately restart the cycle on your next turn.