|First appearance||Brawler to Be|
|Voiced by|| Daichi Endo (Japanese)|
Julien Osen (English)
|(Main attribute used by this battler)||Subterra|
Mason Brown (original version: Bruce Brown (ブルース・ブラウン Burusu Buraun)) is a Subterra brawler from Gundalia, and part of the Gundalian Agents. He seems to be the most calm person of the team when it come to a battle, but when it comes to anything else he freaks out and blames Avior. He also calls his partner "old timer" or "old dog" in many of the episodes.
In Brawler to Be, he battles an unknown kid with a Raptorix and wins. Then, Dan challenges him to a battle, but Jake steps in and wants to prove himself. He defeats him but later loses to Jake in a rematch.
In Confrontation, he and Lena Isis lost to two top-ranked players while using their non-Guardian Bakugan to test their strength. The kids were then brought back to the Twelve Orders and hypnotized by Kazarina in order to recruit them.
In Decoy Unit, he reveals his actual form and is given a second chance by Airzel against Marucho and Jake. The battle ended in a tie after Marucho and Jake fled the battle after Marucho used Akwimos's last ability, which froze Avior and Strikeflier, distracting the Gundalians.
In The Secret of the Orb, Mason heads off with Kazarina, who is sent off with Nurzak on a reconnaissance mission. However, Mason escapes after striking down two Gundalian guards. He then heads off to Neathia, possibly to switch sides, but falls int a large crack in the ground when the Sacred Orb gets "angry" and starts shattering everything. Although Avior saves him from falling, both are sent around the dimensions when the Sacred Orb gave off a massive energy surge.
In Genesis, Mason and Avior are seen stuck in between dimensions along with Nurzak and Sabator. After Dan defeats Dragonoid Colossus, he is brought to Neathia along with Nurzak and joined the Brawlers as they travel to Gundalia. He changes back into his human form again.
In Infiltrated, he, Ren, Nurzak, and Fabia split off from the rest of the Brawlers to rescue his former teammates, Lena, Jesse, and Zenet. Later, he and Ren split off into another group to rescue his teammates while Nurzak and Fabia battled Kazarina and Stoica.
In Final Strike, He leaves the Brawlers to look for Nurzak who he still believes is still alive. He continued to his search of Gundalia for evidence of Nurzak at the end of the episode.
In Gundalian Showdown, Mason was able to find Nurzak and came back just in time to help Fabia defeat Kazarina. Even though he ends only watching Fabia and Nurzak battle, he continues to observe the battle in Broken Spell.
In Code Eve (episode), he, Fabia, and Nurzak rush to Nurzak's ship to go back to Neathia and help the Brawlers fight Emperor Barodius. On the way, they are stopped by Gill and Fabia and Mason fight him in order to buy Nurzak time to start up the ship. In Neathia, he reunites with his former teammates and he was easily defeated by Phantom Dharak when trying to attack Barodius along with the others.
In Destiny Revealed, he was easily defeated by Phantom Dharak when trying to attack Barodius along with the others. Then he leaves with Ren, Lena, Zenet, Jesse, and Nurzak as they all head back to Gundalia.
Mason made his only appearance in Bakugan: Mechtanium Surge along with Avior trying to defend Gundalia from the Chaos Bakugan. He only appeared as an image.
- His surname, like Joe, is Brown, though they are not related.
- He tends to spazz out when things don't go his way (much like Shadow) as he blamed Avior when he lost to Jake and started laughing for no reason when he discovered he was walking in circles.
- He, along with Nurzak joined the brawlers in Episode 29, who are both Subterra brawlers.
- Mason joining the brawlers marks the third time a Gundalian has joined the Battle Brawlers, the others being Nurzak and Ren.
- Dan said both he and Nurzak were sent between dimensions by Barodius. While this is true for Nurzak, this is not entirely true for Mason as it was the Orb that sent him by accident.
- Strangely, the Mason in the anime is a Subterra Brawler, while the Mason in Bakugan Dimensions is a Ventus brawler. It can be noted, however, that these two characters are completely different.
- In episode 36, it was shown that Mason may like Fabia, because he was flirting with her when he arrived with Nurzak, and Avior told him, "Quit flirting, we are here to settle a score". Also, in another episode, he commented about the level 3 Battle Gear ability she used, prompting Avior to ask that if he was jealous.
- Mason and Avior seem to argue a lot Avior thinks Mason is a smart aleck and Mason thinks Avior nags a lot as shown in episode 29.
- His human form seems smaller than his Gundalian form as in, then he transforms from Gundalian to Human form his chest gets smaller and his muscles on his arms get smaller too.
- He is the only member of the Gundalian Agents (excluding Ren) to escape punishment from a Major Twelve Order.
Mason is shown to be a skilled brawler only losing three times against the Brawlers, although one of these losses was on purpose.
Bakugan: Gundalian Invaders
|Unknown Ventus Brawler||4||Win|
|Unknown Darkus & Subterra Brawlers (Tag with Lena)||5||Lose (Deliberate)|
|Casey & Taylor (Tag with Sid)||8||Win|
|Dan Kuso & Shun Kazami (Tag with Taylor)||8||Lose|
|Jake Vallory & Marucho Marukura (Tag with Airzel)||15||Draw|
|Gill (Tag with Fabia)||38||No Outcome|
Bakugan: Mechtanium Surge
|Chaos Bakugan Army (Tag with Jesse)||18||No Outcome|