Omarthis, Ghostfire Initiate + Echoes of Eternity + Mirror Box

Omarthis, Ghostfire Initiate

Echoes of Eternity

Mirror Box

How it works

1. Cast Omarthis either from your hand or from the command zone by paying 2 plus commander tax, if applicable.
2. Echoes of Eternity triggers, copying the Omarthis spell.
3. Resolve the copy of the Omarthis spell, creating a token copy of Omarthis with one +1/+1 counter on it.
4. Resolve the original Omarthis spell, causing it to enter the battlefield with one +1/+1 counter on it.
5. The token Omarthis's first ability triggers twice.
6. Resolve the first trigger, putting a +1/+1 counter on the token Omarthis.
7. The nontoken Omarthis's first ability triggers twice.
8. Resolve the first trigger, putting a +1/+1 counter on the nontoken Omarthis.
9. Repeat from step 5.

This fascinating loop begins the moment you cast Omarthis, Ghostfire Initiate, letting Echoes of Eternity double the spell and forge a token copy alongside your original creature. With Mirror Box nullifying the legend rule, both versions of Omarthis remain safely on the battlefield to feed into one another's growth. Whenever a +1/+1 counter lands on one, Echoes of Eternity steps in once again to double the resulting trigger, allowing the pair to endlessly amplify each other's counters through recursive triggers.