Training Grounds + Eldrazi Displacer + Eyeless Watcher

Training Grounds

Eldrazi Displacer

Eyeless Watcher

How it works

1. Activate Eldrazi Displacer's ability by paying C, blinking Eyeless Watcher.
2. Eyeless Watcher enters the battlefield tapped, triggering itself, creating two 1/1 Eldrazi Scion tokens.
3. Activate an Eldrazi Scion by sacrificing it, adding C.
4. Repeat.
5. Once you have infinite Eldrazi Scion tokens, you may activate any number of them.

This clever loop turns Eldrazi Displacer into an infinite token generator and mana engine by leaning on Training Grounds to heavily discount its blink ability down to just a single generic mana. When you blink Eyeless Watcher, it enters the battlefield to replace itself with a pair of Eldrazi Scion tokens. You can then sacrifice one of those very same Eldrazi Scion tokens for the colorless mana needed to activate Eldrazi Displacer all over again, leaving you with an extra token every single iteration.