Arbor Elf + Freed from the Real + Tropical Island + Utopia Sprawl

Arbor Elf
Freed from the Real
Tropical Island
Utopia Sprawl

Requires
All permanents on the battlefield. Arbor Elf does not have summoning sickness. Freed from the Real attached to Arbor Elf. Utopia Sprawl attached to Tropical Island. "Blue" chosen with Utopia Sprawl.
Steps
  1. Activate Tropical Island by tapping it, adding ug
  2. Activate Arbor Elf by tapping it, untapping Tropical Island
  3. Activate Freed from the Real's second ability by paying u, untapping Arbor Elf
  4. Repeat
Results
Infinite green mana. Infinite blue mana.