Necrotic Ooze + Stern Marshal + Devoted Druid

Necrotic Ooze

Stern Marshal

Devoted Druid

How it works

1. During your precombat main phase, activate Necrotic Ooze using Stern Marshal's ability by tapping it, giving it +2/+2 until end of turn.
2. Activate Necrotic Ooze using Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it.
3. Repeat.
4. Once Necrotic Ooze has infinite toughness, you may instead use Devoted Druid's first ability to get infinite green mana.

By fusing the powers of the grave, Necrotic Ooze becomes an absolute powerhouse once Stern Marshal and Devoted Druid find their way into the graveyard. The Ooze borrows Stern Marshal's tap ability alongside Devoted Druid's self-untap ability, letting you put a -1/-1 counter on itself to untap repeatedly. Because Stern Marshal's pump grants +2/+2 to offset the counter, your Ooze survives the process and grows to infinitely large proportions, allowing you to finally tap for infinite green mana using Devoted Druid's mana-producing ability.