Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + X-23, Deadly Weapon + Phantom Train

Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight

X-23, Deadly Weapon

Phantom Train

How it works

1. Activate Phantom Train by sacrificing the other Mutant.
2. When the Mutant dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. When the Mutant enters, X-23 triggers, putting a +1/+1 counter on X-23 and the other Mutant.
4. Resolve the Phantom Train ability.
5. Repeat.