Time Sieve + Encroaching Mycosynth + Rotlung Reanimator + Maskwood Nexus

Time Sieve

Encroaching Mycosynth

Rotlung Reanimator

Maskwood Nexus

How it works

1. Activate Time Sieve by tapping it and sacrificing five other creatures.
2. When the creatures die as Clerics due to Maskwood Nexus, Rotlung Reanimator triggers five times, creating five 2/2 Zombie creature tokens.
3. Resolve the Time Sieve ability, causing you to take an extra turn after this one.
4. Repeat each turn.

This ingenious engine achieves infinite turns by turning every creature you control into the necessary fuel for Time Sieve. Encroaching Mycosynth ensures all your nonland permanents are artifacts, while Maskwood Nexus simultaneously grants every creature you control all creature types—including Cleric. This transforms any five creatures into the perfect sacrifice fodder; when they die, Rotlung Reanimator triggers to replace them by creating five Zombie tokens. Because Maskwood Nexus also makes those new Zombies into Clerics, you are left with a self-sustaining loop that resets your board and lets Time Sieve grant you an endless succession of extra turns.