Ashaya, Soul of the Wild, Karn, Silver Golem, Basalt Monolith, and Nissa, Who Shakes the World

Prerequisites

• Ashaya, Soul of the Wild on the battlefield
• Karn, Silver Golem on the battlefield
• Basalt Monolith on the battlefield
• Nissa, Who Shakes the World on the battlefield
• available

Steps

1. Activate Karn 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. Nissa triggers, adding
4. Activate Basalt Monolith's second ability by paying , untapping it
5. Repeat from step 2

Results

• Infinite colorless mana
• Infinite green mana