Requires

Cloudstone Curio must be on the battlefield. Phyrexian Altar must be on the battlefield. Master of Waves must be in hand. Your devotion to blue is at least three. Mana needed:

Steps

1. Cast Master of Waves by paying .
2. When Master of Waves enters the battlefield, it and Cloudstone Curio trigger.
3. Resolve the Cloudstone Curio trigger, choosing to return nothing to your hand from the battlefield.
4. Resolve the Master of Waves trigger, creating a number of 1/0 Elemental creature tokens equal to your devotion to blue.
5. When the Elementals enter the battlefield, Cloudstone Curio triggers that many times.
6. Holding priority, activate Phyrexian Altar by sacrificing all Elemental tokens, adding that much .
7. Resolve the first Cloudstone Curio trigger, returning Master of Waves to your hand from the battlefield.
8. Resolve all remaining Cloudstone Curio triggers, choosing to return nothing to your hand from the battlefield.
9. Repeat.
10. If your devotion to blue excluding Master of Waves is at least four, this combo will net infinite colored mana.

Results