Hey!! I wasn't done explaining things! OK. I see how it is. Go on. Leave me. Friendless and alone...
—RoboKing, Katamari Forever
After the King woke up from his extended slumber, RoboKing goes on a rampage again after realizing that he is now useless. When the King finds out that he has a replica, he orders the Prince to dismantle RoboKing's core. This is accomplished (of course), by rolling a Katamari around the restrained RoboKing until large enough to roll up the core that The Prince made earlier. However, when the game is finished and the Katamari Drive mode has been unlocked, RoboKing has been reassembled, and is being threatened by the King to make more stars. RoboKing's kindness towards the Prince is most likely due to the fact that he was created by the Prince. It could also hint at how the Prince wants his father to be, or simply the Prince sees past the King's aggression and knows that his father does love him (and is only pushing him to do better).
RoboKing does not use the royal "we" like the King, and tends to be less aggressive. He wants to be nice to The Prince/Cousins which is hinted at by his telling the roller to "please" go roll a Katamari. He also wants The Prince or Cousins to be better than him when he says "...leave being OK to me."
- At the heel of his foot, he's branded as "Cosmo" in Namco font.
- During the 'Farewell!' stage, as RoboKing's interior is revealed when rolling up roboparts, it's revealed that he has random objects under everything, such as fruits and art supplies.
- When 'angry' or in 'danger mode', his eyes turn red, changing from the usual yellow.
- According to each robopart description, every cousin contributed to RoboKing's creation.
- RoboKing is seemingly a foil character to The King of all Cosmos, depressed and self-deprecating as the King has a large ego and speaks about himself in a good light often.
- When ignored during the intro of a level or when worried, he makes soft metal screeching noises.
- In Tap My Katamari, he is seen celebrating with Papa and the Queen whenever you pass a level. He also appears if the Cosmic Mushroom is purchased.