Felidar Guardian + Valkyrie's Call + Conspiracy + Umbral Collar Zealot

Felidar Guardian

Valkyrie's Call

Conspiracy

Umbral Collar Zealot

How it works

1. Activate Umbral Collar Zealot by sacrificing Felidar Guardian.
2. When Felidar Guardian dies, Valkyrie's Call triggers, returning Felidar Guardian from your graveyard to the battlefield as an Angel.
3. When Felidar Guardian enters the battlefield, it triggers, blinking Conspiracy. Choose any creature type except "Angel" as Conspiracy enters the battlefield.
4. Resolve the Umbral Collar Zealot ability.
5. Repeat.

This clever loop transforms your battlefield into a self-sustaining engine by rewriting the very nature of your creatures with Conspiracy, choosing any type other than "Angel" to start the magic. When you feed Felidar Guardian to Umbral Collar Zealot's sacrifice outlet, Valkyrie's Call steps in to immediately resurrect it as an Angel, bypassing its normal death because it is no longer bound by its original creature types. That resurrection triggers Felidar Guardian's entry ability to blink Conspiracy, letting you reset or re-declare its type if needed while generating an endless chain of entering-the-battlefield, leaving-the-battlefield, and death triggers.