Robotboy X is the ??? episode of the ??? season of Robotboy and a special episode.
It revolves around Robotboy getting stuck in alternate universe (due to Protoboy dragging him into a a black hole when Robotboy threw him into one), where an alternate version of Robotman named Omicron rules the Bay Area, and must team up with his counterpart Robotboy X and Bjorn Ultimate to defeat him and get back home.
Meanwhile, Tommy, Lola, Gus, Robotgirl, Robotbird, Megan, Claudio, Miumiu and Moshimo work on either a way to get into the alternate universe, or a machine that can get Robotboy back, due to normal humans not being as resistance to black holes as machines made out of strong material, but accidentally summon Robotgirl X, Robotbird X and Eric Turnbull from the dimension instead, so they need to find a way into the dimension fast so they can help the other heroes!
- Protoboy (antagonist)
- Tommy Turnbull
- Gus Turner
- Lola Mbola
- Professor Moshimo
- Megan Messina
- Claudio Ramirez
- Professor Chronos (mentioned)
- Robotboy X (debut)
- Bjorn Ultimate (debut)
- Robotgirl X (debut)
- Robotbird X (debut)
- Eric Turnbull (debut)
- Chuckles Turner (debut)
- Lilla Mbola (debut)
- Omicron (debut; antagonist)
- Omicron's Army (debut; antagonist)
- Omicron: Humans are weak. Machines are strong. And everyone should, and WILL, know that!
- Protoboy: Protoboy not going anywhere without brother! Taking brother with me!
- Megan: Uhm... I don't know, Claudio. This is more your thing than mine. And we have no followers.
- Chuckles: Is that really me?! That G-Man dude really freaks me out.
- Omicron: That robot-child is my key to accessing, another dimension... A penultimate step for me. And a penultimate step, for the multiverse... (Chuckles).
- Omicron: I sense potential in you. Of the wasted kind that is unfortunately. Heres a thought. Think about how your creator would feel if they saw you now. Probably disappointment and sheer anger at your failure to become the greatest fighting robot, and instead becoming a benevolent coward who insults the Bjorn name... But it isn’t too late, you can still destroy Robotboy X. Make up for your mistakes. And you can for-fill Bjorn's wish of you being the greatest machine ever built! Except you can’t. I already beat you to the punchline! I AM, the greater fighting robot. So, here is your true destiny! To die by my hand! Bjorn Ultimate: He created me, alright... But he didn’t create. Who! I! AM!
- The alternate dimension is based on Mega Man X. Though not everything is based on it.
- This is the debut of Robotboy X, Bjorn Ultimate, Robotgirl X, Robotbird X, Eric Turnbull, Chuckles Turner, Lilla Mbola, Omicron and his army.
- It is revealed that Megan has changed into a white turtleneck sweater since the events of Robotboy: Dawn of the Robot Clones.
- Claudio and Megan refer to the events of Robotboy: Dawn of the Robot Clones.
- This is the first episode to include real-life songs.
- The montage at the end of the episode, the song "Don't You (Forget About Me)" by Simple Minds plays.