Necrotic Ooze + Stern Marshal + Devoted Druid

Prerequisites

• Necrotic Ooze does not have summoning sickness.
• It is your precombat main phase.

Steps

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

Effects

• Infinite green mana
• Infinitely large creature until end of turn