The Jolly Balloon Man + Felidar Guardian + Doubling Season

The Jolly Balloon Man

Felidar Guardian

Doubling Season

How it works

1. Activate a permanent you control by tapping it, adding at least 1.
2. Activate The Jolly Balloon Man by paying 1 and tapping it, creating two token copies of Felidar Guardian that are 1/1 Balloons with haste.
3. When the Felidar Guardian tokens enter the battlefield, they trigger, blinking the mana-producing permanent and The Jolly Balloon Man.
4. Repeat.

This loop takes flight by using The Jolly Balloon Man to copy Felidar Guardian, but Doubling Season ensures you get two copies of the Guardian instead of just one. When this pair of Felidar Guardian tokens enters the battlefield, their triggers let you blink both The Jolly Balloon Man and whatever mana source fueled the activation—readying them to repeat the process. Because you are left with an extra token each iteration that isn't needed for the next blink, you can easily accumulate an infinite army of flying, hasty Balloon creatures alongside endless entry and sacrifice triggers.