Yedora, Grave Gardener + Primordial Mist + Walking Ballista

Yedora, Grave Gardener

Primordial Mist

Walking Ballista

How it works

1. Cast Walking Ballista for X = 0.
2. Walking Ballista dies to having zero toughness.
3. Yedora triggers, returning it to the battlefield face-down as a Forest land.
4. Tap that Forest for .
5. Activate Primordial Mist by exiling the face-down Walking Ballista, and allowing you to cast it this turn.
6. Repeat.
7. Once you have infinite , you may cast Walking Ballista using an arbitrarily large amount of mana, and then use its second ability to deal an arbitrarily large amount of damage to any target(s).