Umbral Mantle, and Accomplished Alchemist

Prerequisites

• Umbral Mantle on the battlefield
• Accomplished Alchemist on the battlefield
• undefined

Steps

1. Activate Accomplished Alchemist by tapping it, adding at least three mana of any color
2. Activate Accomplished Alchemist 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