Rings of Brighthearth, Deserted Temple, and Tolarian Academy

Prerequisites

• Rings of Brighthearth on the battlefield
• Deserted Temple on the battlefield
• Tolarian Academy on the battlefield

Steps

1. Activate Tolarian Academy by tapping it, adding at least
2. Activate Deserted Temple's second ability by paying and tapping it, targeting Tolarian Academy
3. Rings of Brighthearth triggers, causing you to pay to copy Deserted Temple's ability, targeting Deserted Temple
4. Resolve both Deserted Temple abilities, untapping Deserted Temple and Tolarian Academy Repeat

Results

• Infinite blue mana
• Infinite mana lands you control can produce
• Infinite untap of lands you control