Mana Echoes + Phyrexian Altar + Lab Rats

Mana Echoes

Phyrexian Altar

Lab Rats

How it works

1. Cast Lab Rats with buyback by paying 4, creating a 1/1 Rat creature token and returning Lab Rats to your hand.
2. When the Rat enters the battlefield, Mana Echoes trigger, adding C for each Rat you control.
3. Activate Phyrexian Altar by sacrificing the Rat, adding .
4. Repeat.
5. If you control four or more Rats as the combo begins, this combo nets infinite colorless mana.

This clever loop relies on Mana Echoes to turn a humble rodent into an explosive mana engine, scaling up its colorless output with every iteration as your colony grows. By channeling Phyrexian Altar, you can instantly convert that newly spawned vermin into the black mana needed to fuel the next cycle. Finally, Lab Rats provides the repeatable casting engine, utilizing its buyback cost to return straight to your hand so you can flood the board over and over again.