Actor Allusion: This isn't the first time Brad Jones and Ed Glaser donned a red gi and a camo gi respectively, and squared off in an ultimate showdown. They previously did so in the Kung Tai Ted videos on the Ninja Death trilogy, where Brad played the titular Ted and Glaser played Master Kempo Dojo.
When Andy Chworowski cameoed, he asked "What's a ninja?" as in Ninja The Protector.
Technology Marches On: Where Gordon and his wife record themselves on VHS, their son is a portable DVD player.
Devouring Gordon's photograph after being unable to tear it up.
Devouring the cookie he used to wipe his face with during the training montage.
Additionally, Brad wasn't originally meant to dub Bruce's voice himself, but after submitting a performance based on the villain Solomon in Godfrey Ho's Thunder of the Gigantic Serpent, he got the dub job as well.
Season 2 adds smearing the remains of a pie on his face to the pile of Brad Jones ad-libs.