- Jax was designed by Ezreal (person).
- Jax is voiced by Erik Braa, Who also voices .
- Jax's name may derive from the Greek warrior Ajax.
- Jax's background does not reveal where he came from before he joined the League.
- Jax's outward appearance resembles the look of the "Garo ", a ninja-like tribe in "The Legend of Zelda: Majoras Mask".
- Vandal Jax does not appear to be related to the gang that has surfaced among the other champions with the vandal skins such as , , and . This is further supported by its release date, which preceded the other Vandal skins by a significant amount.
- Jaximus is a reference to the Murmillo, a gladiator class from the Roman Imperial Age.
- It might also be a reference to Maximus, the protagonist of the movie 'Gladiator', although Maximus wields a sword, rather than a polearm.
- This skin features a memorial tribute to Joe, a Ewings Sarcoma patient who visited Riot thanks to the Make A Wish Foundation. Joe passed away on July 13, 2012. The movement quote for the Jaxiumus skin, Joe's favorite, was changed to "Here's to you, kid!" in his memory.
- PAX Jax is a reference to the Cardboard Tube Samurai from the web comic Penny Arcade (which hosts the Penny Arcade Expo - PAX). A symbol on the skin resembles Pac-Man and matches symbols on the Samurai's gi and the shirt of Penny Arcade protagonist Gabe.
- The Mighty Jax is a reference to 90's Disney Film The Mighty Ducks.
- Jax is ' drinking buddy.
- Jax was placed into the League by High Councilor Reginald Ashram, the former leader of the League. Ashram went missing shortly before Jax's arrival.