Gilder Bairn + Gemstone Array + Utopia Vow

Gilder Bairn

Gemstone Array

Utopia Vow

How it works

1. Activate Gilder Bairn using its ability from Utopia Vow by tapping it, adding one mana.
2. Activate Gilder Bairn by paying 2G/U and untapping it, doubling each counter on Gemstone Array.
3. Activate Gemstone Array as many times as necessary by removing counters from it, adding at least two mana.
4. Repeat from step 2.
5. Once you have infinite counters on Gemstone Array, you may instead double the counters on any other permanents.