The Earthen Ally is a humble 0/2 for one Green mana, gaining power for each color among Allies you control
When you prevent yourself from traveling the usual path in your deck building process, chances are youll arrive at a totally new destination
Featuring the unnamed gating mechanic that forced you to return a permanent of the same color to your hand upon entering, that so-called drawback didn't hurt the Wurm's playability, as getting back a Blastoderm that was about to die from fading or returning a Thornscape Battlemage to reuse its kicker abilities was nothing but a benefit
Until then, may you find your own favorites of Gatecrash
A dedicated UR build can load the graveyard very easily with self-mill and looting effects, so I could even see Eris hitting play around the same time as Stella despite the huge gap in mana cost
Its the kind of complexity you expect from a Modern Horizons 2 Mythic