Rockilla was collecting Stardust to try and go from Common to Cosmic when Thunder Eagle stole the Stardust from him. Rockilla followed her to her Thunder Habitat, where they wrestled to get a hold of the precious resource. Rockilla won and swallowed the Stardust inside the Thunder Habitat but, instead of an enhanced Earth Rockilla, he became Thunderkong!
Behold, the Lagerchaun of all Cosmics! Thunderkong, like his past self, is still garbage. He has decent Power for an Attacker, but his other stats are just horrible. His Stamina costs are ludicrous, meaning he cannot chain attacks infinitely, and his damage output is awful, beaten by most Cosmics who aren't even Attackers. Not even his extra turns can save his damage output as they deal pathetically little damage. If that wasn't enough, his best self-Support skill Shocks himself, which is absurd considering he's an extra-turner. Furthermore, his trait is next to useless, not protecting him from anything at all, and his only saving grace is his Relic slots, which don't even help him deal damage. Overall, Thunderkong is easily the single-worst Cosmic to ever exist in Monster Legends. You're better off using any other Original Mythic over this sorry excuse of an Attacker.