Cayth, Famed Mechanist + Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Phyrexian Altar

WUBR identity

Commander legal

The 3 combo pieces

How to execute it

  1. Activate Phyrexian Altar by sacrificing Cayth.
  2. When Cayth dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
  3. When Cayth enters, its fabricate ability triggers, putting a +1/+1 counter on it.
  4. Repeat.

What the combo produces