Appa, Steadfast Guardian + Umori, the Collector + Felidar Guardian + Thornscape Familiar

Appa, Steadfast Guardian

Umori, the Collector

Felidar Guardian

Thornscape Familiar

How it works

1. Cast Appa by paying
2. When Appa enters, its first ability triggers, exiling Felidar Guardian with the ability to cast it later from exile.
3. Cast Felidar Guardian from exile by paying 0.
4. Appa's second ability triggers, creating a 1/1 Ally creature token
5. When Felidar Guardian enters, it triggers, blinking Appa.
6. Repeat from step 2.

This crafty loop turns Appa, Steadfast Guardian into an engine for infinite value, letting you cycle between exile and the battlefield endlessly. The magic happens because Thornscape Familiar and Umori, the Collector (naming creature) stack their cost reductions so aggressively that Felidar Guardian's exile-cast cost of {2} is completely wiped out, allowing you to recast the cat for free every time Appa airbends it. Each iteration triggers Appa's token generation to flood the board while repeating the enter-the-battlefield dance, creating an unstoppable chain reaction of triggers.