Blitser is a Subterra Burst bakugan and John's guardian.
Blitser was created by Freedom Dragonoid which meant he was born a Burst bakugan.This was after the war against Fear. He was in a constant search for any others of his kind even though he knew he was the only one. When The Final Crush was created he was sent to John to defend all of the Vestroias and Earth. He and John got to a bad start when they got into constant arguments. Though along the way they began to become best friends. They soon trusted eachother enough that they would completely go along with eachothers actions. This includes when John betrayed The Burst Brawlers to help G-2000. When he and John came back to help the others Blitser became the first to evolve while fighting Final Crush. He became RockSlide Blitser.
In ball form he looks like Flare Dragaon with Subterra colors and Burst Bakugan colors In bakugan form he looks like Dharak with Subterra colors.