Creature spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting a creature spell pays for or one mana of that creature's color.)
At the beginning of your first main phase, you may pay . If you do, transform Eirdu.
Flying, lifelink
Each other nontoken creature you control has persist. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)
At the beginning of your first main phase, you may pay . If you do, transform Isilu.
Flood the board with creatures cheaply using convoke from the Eirdu side, then flip to Isilu to blanket your team in persist for resilient, recursive value. You sacrifice and reanimate creatures repeatedly for engine triggers and grind opponents out, while lifelink keeps you safe. The deck wins by snowballing creature-based value and converting persist loops into a kill.
Convoke makes wide boards and big creatures absurdly cheap to deploy
Persist gives a built-in graveyard/sac engine that punishes board wipes and removal
Innate flying, lifelink, and evasion on a resilient commander stabilize the board
Excellent at aristocrats loops since persist creatures die and return repeatedly
The flip is symmetrical timing-locked to your main phase, so it's slow to toggle modes
Persist creatures come back with -1/-1 counters, weakening repeated value without counter removal
Relies on having creatures already in play for convoke to matter
Vulnerable to graveyard hate and exile-based removal that sidesteps persist
Prevents the -1/-1 counter so persist creatures return endlessly for true infinite loops.
Add free sacrifice outlets (Carrion Feeder, Ashnod's Altar) and drain payoffs to convert persist into a true combo kill, and run Solemnity or Mikaeus to enable infinite loops. Improve mana with better ramp and recursion like Reanimate and Victimize to cheat bombs into play faster. Tighten the curve toward impactful ETB creatures that maximize convoke and persist re-triggers, and add graveyard protection against hate.
Legendary Creature — Elemental God // Legendary Creature — Elemental God
or one mana of that creature's color.)