Bjorn Ultimate is the creation of Bjorn Bjornson from an alternate universe, who created him to be the true robot who could destroy Robotboy and become the greatest fighting robot in the world. Though Bjorn Ultimate never got to see the original Robotboy in person until later, due to Omicron's attack on Bjorn's mansion, which ended with the fusion of Bjornbot and Omicron, and the seeming death of Bjorn Bjornson. Bjorn Ultimate was kept hidden underneath the mansion, until Omicron found him and tried to destroy him, but Ultimate escaped, though damaged.
Sometime later, he met Robotboy X. Remembering what he was told about him, fought Robotboy, but realized he had been lying to him. So he befriended Robotboy X, apologized for attacking him and reformed. He has been friends with him since.
He is voiced by Rupert Degas.
He resembles Bjornbot's superactive mode, but his eyes are normal, his skin is human colored, he wears a helmet, and he is thinner. And as this is his normal mode, he doesn't appear transformed, his torso not having the split in it for example. He usually has a lightsword he uses for combat with him.
Bjorn Ultimate was
He doesn’t know too much about the world around him, and is curious about it. He is also caring to people, though Bjorn forbade him from acting this way to people other then him, in threat of reprogramming Ultimate to be a mindless machine who was only to serve Bjorn. He obeyed and eventually stopped being caring to people, though he later came back to his senses when he realized Robotboy was not as bad as Bjorn made him out to be. He can also be rather stoic.
- ......What?!... You aren’t, a-as b... Bad as he, made you.... Out to, be...? (Upon realising Robotboy X isn’t as bad as he was told).
- He created me, alright... But he didn’t create. Who! I! AM! (His response to Omicron when he insulted his past).
- He is based on Zero from the Mega Man X series.