Wasn't sure if I should just put this in the "Comments That Don't Warrant a Thread" thread, but I ultimately decided that this was newsworthy enough to warrant its own thread (if it's true, that is).
Footage:
Quote from 2016:
“But you never know, I could pop up here and there. Let me explain that to you even better. It’s not going to even be televised, it’s going to be me in a ninja f–king outfit wrestling one of my buddies and nobody’s ever going to know. It’s going to be very ‘Monty Python’ so to speak.”
Confirmation?
https://wrestlingnews.co/other/it-looks-like-cm-punk-returned-to-wrestling-under-a-mask-last-night/
There's supposedly an Instagram picture of Punk in the same outfit, sans the mask, but someone else will have to sleuth that out.