The third oldest of Jack's Alter Egos, Marvin the Magnificent is a showman and aspiring magician. Though he went by the title "Jack The Magnificent" in his first appearance, "The Jacksepticeye Power Hour | Marvin's Magic", Jack himself later renamed him Marvin as tribute to the name of the performance (in "So Much Fanart | Septic Art").
Marvin is somewhat more cynical than his creator, approaching things that annoy him with a straightforward, sarcastic wit or simply deadpan resignation. Because of his short attention span, several things can annoy him in a matter of minutes and he is not easily impressed. He does, however, possess Jack's usual confidence and is committed to his quest for amazing his viewers. Sometimes, however, he questions himself and his life choices, wondering why he doesn't have any friends and if he should have become an artist instead.
Clear and methodical, Marvin isn't good at improvisation and reads instructions carefully, hoping to perform it right the first time. He scorns science and even announces that he laughs in the face of it, preferring what he considers a grander job. He sees magic as a viable field that deserves proper treatment; he insists that he dress and act the part and becomes dismayed when he lacks the proper tools he needs to charm his audience. However, he warns that it is based on lies and should never be taught to children in schools.
Very little is known about Marvin's backstory and personal life: His birthday is August 11, 2016. He has a grandmother who relies on medication for her mental health and a bad hip. He also has a fondness for sushi and calls his magician mask "Mr. Fluffington", taking the time to decorate it, though he can become disoriented at the smell of art supplies.
- In the videos "AM I COLOUR BLIND? | Colourblind Test" and "THANOS INFINITY GAUNTLET MODE | Fortnite Battle Royale" Marvin's mask is shown hanging by Jack's whiteboard in the background.