Biotransference + Helm of the Host + Master of Waves + Time Sieve

UB identity

Commander legal

The 4 combo pieces

What must be in place

Helm of the Host attached to Master of Waves.
Your devotion to blue is at least four.

How to execute it

  1. At the beginning of your combat phase, Helm of the Host triggers, creating a token copy of Master of Waves with haste.
  2. The Master of Waves token triggers, creating a number of 1/0 Elemental creature tokens equal to your devotion to blue.
  3. Activate Time Sieve by tapping it and sacrificing five creature tokens, causing you to take an extra turn after this one.
  4. Repeat each turn.

What the combo produces