Umbral Mantle, and Metalworker

Prerequisites

• Umbral Mantle on the battlefield
• Metalworker on the battlefield
• undefined

Steps

1. Activate Metalworker by tapping it, revealing at least two artifact cards from your hand and adding at least
2. Activate Metalworker 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 colorless mana