A Royale Pain is the 10th episode of Bakugan: Mechtanium Surge. It aired on April 17th, 2011.
Shun has been battling far more frequently since taking the position of leader of the Brawlers, and it's starting to take its toll on him. However, he is more determined than ever to put a stop to the chaotic battling when Mechtogans are allowed in battles and Shun decides to enter the Battle Royale to stop them. Things get tough when he goes up against Robin from Team Anubias and Soon from Team Sellon, who each uses Bolcanon and Krowll, each equipped with their BakuNanos, Hyper Pulsor and Slicerix. Shun and Taylean fight them but start losing. Shun and Taylean fight on. However, Taylean spawns a Mechtogan called Silent Strike, making things even more complicated. Shun tries his best to defeat it to no avail, and Silent Strike defeats both Bolcanon and Krowll. Shun is then rescued by Rafe and Paige with their Bakugan, Boulderon and Wolfurio. After Silent Strike flees, Rafe and Paige reveal that they are a Neathian and Gundalian, respectively. They tell Shun and Marucho that the Mechtogan are the offspring of chaos when there is a lack of sync between a brawler and their Bakugan. They also say that Princess Fabia has sent them to learn from the Brawlers. Shun however, refuses their help and leaves while Marucho's father asks him to quit the Brawlers, surprising Marucho.
- Shun vs two unknown kids (under Mag Mel's control): Shun Wins
- Sellon vs three unknown kids (under Mag Mel's control): Sellon Wins
- Anubias vs three unknown kids (under Mag Mel's control): Anubias Wins
- Battle Royale: Shun vs Robin vs Soon vs other unknown kids: Shun Wins (after spawning Silent Strike)
- Shun, Paige, and Rafe vs Silent Strike: No Outcome (Silent Strike teleported away)
- Rafe and Paige were sent by Fabia Sheen to help the brawlers. Shun, however, refuses their help.
- Rafe reveals the reason of spawning a Mechtogan to Shun and Marucho.
- Titanium Dragonoid
- Cyclone Percival
- Flash Ingram
- This marks the first time since Underground Take Down that a true form of a Bakugan (in this case, a Mechtogan) is seen in the Intermission Screen alongside its toy equivalent.
- Strangely, the season's logo do not appear in this episode in the English version.
- Even though Dan was disqualified for using Mechtogan in his battle with Anubias, Sellon, Shun and Anubias weren't disqualified when they used their Mechtogan and instead took the win. This could mean that Interspace's Computer Administration has now allowed Mechtogan to be used with no disqualification.
- Marucho's father makes his first appearance since season 1.
- This is one of the few episodes (at least in the original version) of Season 4 where OST from Season 1 and 2 is used (specifically Runo's Theme when Soon summons Slicerix BakuNano).
- During the battle royale, Soon activates Screw Ripper for Krowll, but instead says Bolcanon's ability, Pummel Bouler instead. The reverse is also true for Robin. This does not occur in the original version.