Fanatic of Rhonas, and Umbral Mantle

Prerequisites

• Fanatic of Rhonas on the battlefield
• Umbral Mantle on the battlefield
• Umbral Mantle attached to Fanatic of Rhonas
• Fanatic of Rhonas does not have summoning sickness
• You control a creature with power 4 or greater

Steps

1. Activate Fanatic of Rhonas's second ability by tapping it, adding
2. Activate Fanatic of Rhonas using the ability from Umbral Mantle by paying and untapping it, giving it +2/+2 until end of turn
3. Repeat

Results

• Infinitely large Fanatic of Rhonas until end of turn
• Infinite green mana