Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Phyrexian Altar + Strangleroot Geist

WBG identity

Commander legal

The 3 combo pieces

• Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight
• Phyrexian Altar
• Strangleroot Geist

How to execute it

1. Activate Phyrexian Altar by sacrificing Strangleroot Geist
2. When Strangleroot Geist dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
3. Activate Phyrexian Altar by sacrificing Strangleroot Geist
4. When Strangleroot Geist dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
5. Strangleroot Geist enters and dies as a state-based action due to having 0 toughness. Its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
6. Repeat from step 3.

What the combo produces

• Infinite colored mana
• Infinite creature LTB
• Infinite death triggers
• Infinite ETB
• Infinite sacrifice triggers