Agatha's Soul Cauldron + Wildwood Mentor + Ashnod's Altar + Thopter Squadron

Agatha's Soul Cauldron

Wildwood Mentor

Ashnod's Altar

Thopter Squadron

How it works

1. Activate Wildwood Mentor using Thopter Squadron's first ability by paying 1 and removing a +1/+1 counter from it, creating a 1/1 Thopter artifact creature token.
2. When the Thopter enters the battlefield, Wildwood Mentor's first ability triggers, putting a +1/+1 counter on itself.
3. Activate Ashnod's Altar by sacrificing the Thopter, adding CC.
4. Repeat.
5. Once you have infinite mana, you may forego sacrificing the Thopters.
6. Once you have infinite creature tokens, you may activate Wildwood Mentor using Thopter Squadron's last ability any number of times.

This clever loop turns Thopter Squadron into a self-sustaining token generator by leveraging Agatha's Soul Cauldron to grant its activated abilities to Wildwood Mentor, letting the Mentor spend just {1} to produce a Thopter. Each time a token arrives, Wildwood Mentor's own trigger counters its cost by placing a +1/+1 counter back onto itself, fueling the next activation. Ashnod's Altar then converts those generated Thopters into a surplus of colorless mana, which can easily be filtered into any color thanks to the mana-fixing granted by Agatha's Soul Cauldron.