Umbral Mantle, and Deathbloom Ritualist

Prerequisites

• Umbral Mantle on the battlefield
• Deathbloom Ritualist on the battlefield
• undefined

Steps

1. Activate Deathbloom Ritualist by tapping it, adding at least three mana of any color
2. Activate Deathbloom Ritualist by paying and untapping it, giving it +2/+2 until end of turn
3. Repeat

Results

• Infinite power for a creature until end of turn
• Infinite colored mana