Training Grounds, Basalt Monolith, and Karn's Touch

Prerequisites

• Training Grounds on the battlefield
• Basalt Monolith on the battlefield
• Karn's Touch in hand
• Basalt Monolith does not have summoning sickness
• available

Steps

1. Cast Karn's Touch by paying , causing Basalt Monolith to become an artifact creature until end of turn
2. Activate Basalt Monolith's first ability by tapping it, adding
3. Activate Basalt Monolith's second ability by paying , untapping it
4. Repeat

Results

• Infinite colorless mana