Agatha's Soul Cauldron + Wildwood Mentor + Phyrexian Altar + Triskelavus

Agatha's Soul Cauldron

Wildwood Mentor

Phyrexian Altar

Triskelavus

How it works

1. Activate Wildwood Mentor using Triskelavus's first ability by paying 1 and removing a +1/+1 counter from it, creating a 1/1 Triskelavite artifact creature token.
2. When the Triskelavite enters the battlefield, Wildwood Mentor's first ability triggers, putting a +1/+1 counter on itself.
3. Activate Phyrexian Altar by sacrificing the Triskelavite, adding 1.
4. Repeat.

This ingenious loop relies on Agatha's Soul Cauldron granting Triskelavus's counter-removal and token-creation ability to Wildwood Mentor, turning the Mentor into a self-sustaining engine. By paying {1} to produce a Triskelavite token, you immediately trigger Wildwood Mentor's ability to replace the counter it just spent. Feeding that newly minted token into Phyrexian Altar generates the exact mana needed to keep the cycle going, yielding infinite creature entry, exit, sacrifice, and death triggers across legal formats like Commander and Legacy.