Shrek

Shrek is a green ogre and the main character of DreamWorks' Shrek film series. In SuperMarioGlitchy4's videos, he only appeared in "Cooking with Bowser and Mario 2!" and a few cameos in Retarded64: Mario for Hire. and archival footage from SM64: The Retardness of 2014.

Physical Description
Shrek is a green ogre wearing a white pullover, brown trousers, a brown belt, and black boots.

Appearances in SuperMarioGlitchy4's videos
Following his debut, Shrek only appeared in cameos and archival footage.

Cooking with Bowser and Mario 2!
This is Shrek's first and most prominent appearance in SMG4's bloopers. In this video, he was created as a result of a chemical reaction that occurred after Mario added a Super Mushroom to a bowl of presumably unfinished Tubby Custard. Shrek then proceeded to rape Bowser, destroy Mario's restaurant, Cafe Mario, knock a red Yoshi out of his chair, hit SMG4, dance with Waluigi, and dance with the girls from the original Caramelldansen video before rocketing out of the building towards the moon, all to the song Caramelldansen. Later, Mario is traumatized because he believes Tinky Winky and Shrek are connected to the Illuminati.

Retarded64: Mario for Hire.
Shrek makes two other cameo reappearances in this other video for a few seconds, both at the "Super Mario Business Time" in an office, on his computer at the background. The first time is when the phone is ringing, and the second is when Trevor Phillips (a man coming from the video game Grand Theft Autos V (GTA V for short)) accidentally kills Mega Man Volnutt with a gun when he tries to assassinate Mario.

SM64: The Retardness of 2014
In this blooper, Shrek makes a cameo appearance in a clip from the video "Cooking with Bowser and Mario 2!" mentioned by Bowser.

Trivia

 * Shrek apparently has the power of Caramelldansen as seen in his debut.