What a showcase of game dev mechanics! HAHA Love it.
Using a time loop of recorded events from each play-through.
Count-down timer (classic!)
FPS mechanics.
Particle effects
Rigidbodies and triggers.
Render Textures for picture in picture, or should I say Game In Game!
Cryaon Drawing with a mask.
Screen Capture with the camera
Audio manipulation (how did you get it to always sound so good when it plays?!)
Platform mum jumping (that one was a bit tricky)
Nice stuff! Should we expect a video on the making of this game?