Dragonback Assault + Bladewing's Thrall + Ashaya, Soul of the Wild + Lithatog

Dragonback Assault

Bladewing's Thrall

Ashaya, Soul of the Wild

Lithatog

How it works

1. Cast Bladewing's Thrall by paying 2.
2. When Bladewing's Thrall enters, Dragonback Assault triggers, as Bladewing's Thrall is a land due to Ashaya.
3. Holding priority, activate Lithatog by sacrificing Bladewing's Thrall.
4. Resolve the Dragonback Assault trigger, creating a 4/4 Dragon creature token.
5. When the Dragon enters, Bladewing's Thrall triggers, returning itself from your graveyard to the battlefield.
6. Repeat from step 2.

This fascinating loop relies on Ashaya, Soul of the Wild to fundamentally alter the battlefield, turning your nontoken creatures into Forest lands that trigger Dragonback Assault whenever they enter. That continuous landfall trigger generates a 4/4 red Dragon token, which in turn satisfies the condition for Bladewing's Thrall to pull itself right back out of your graveyard. Meanwhile, Lithatog acts as the sac outlet by feeding on Bladewing's Thrall while simultaneously growing infinitely large, turning a neat permanent-type interaction into a non-stop engine of endless triggers.