Sprout Swarm + Ashnod's Altar + Quina, Qu Gourmet

Sprout Swarm

Ashnod's Altar

Quina, Qu Gourmet

How it works

1. Cast Sprout Swarm with buyback by paying at most 4, creating two creature tokens and returning Sprout Swarm from the battlefield to your hand.
2. Cast Sprout Swarm with buyback by paying at most 3 and tapping two creature tokens, creating two creature tokens and returning Sprout Swarm from the battlefield to your hand.
3. Activate Ashnod's Altar twice by sacrificing two tapped creature tokens, adding CCCC
4. Repeat from step 2.

This clever loop turns Sprout Swarm into a self-sustaining engine by taking advantage of its buyback cost alongside the token-doubling presence of Quina, Qu Gourmet. Whenever you cast Sprout Swarm, Quina ensures you get both a Saproling and an extra Frog token, providing two bodies to sacrifice to Ashnod's Altar for four colorless mana. That mana more than covers the spell's total cost—including its buyback—while convoke lets you tap the newly generated tokens to pay for the rest, leaving you with an ever-growing surplus of mana and an infinite storm count.