Progenitor Mimic + Timeless Witness + Walk the Aeons

GU identity

Commander legal

The 3 combo pieces

What must be in place

Enough mana available to cast the extra turn spell each turn.
Progenitor Mimic is a copy of Timeless Witness.

How to execute it

  1. Cast Walk the Aeons by paying its mana cost, taking an extra turn after this one.
  2. At the beginning of your next upkeep, Progenitor Mimic triggers, creating a token copy of Timeless Witness.
  3. When the token Timeless Witness enters the battlefield, it triggers itself, returning Walk the Aeons from your graveyard to your hand.
  4. Repeat.

What the combo produces