Kurkesh, Onakke Ancient, Grim Monolith, and Mycosynth Lattice

Prerequisites

• Kurkesh, Onakke Ancient on the battlefield
• Grim Monolith on the battlefield
• Mycosynth Lattice on the battlefield
• available

Steps

1. Activate Grim Monolith's first ability by tapping it, adding
2. Activate Grim Monolith's last ability by paying
3. Kurkesh triggers, causing you to pay to copy Grim Monolith's last ability
4. Resolve the copy of Grim Monolith's last ability, untapping it
5. Activate Grim Monolith's first ability by tapping it, adding
6. Resolve the Grim Monolith ability from step 2, untapping it
7. Repeat

Results

• Infinite colored mana
• Infinite colorless mana