His castle is in a far galaxy, connected by the portal of the Golden Key. When you have defeated all three planets (fire, ice, jungle) and have all three knights, go to the Giant Asteroid at X-11 Y-84 to reach the portal.
(see related question)
on astro knights island
It is on tp of the castle roof in astro knight island
The castle is the second area on the island, to the right of the Village.
Once you have built a new spaceship on Astro Knights Island, it will park on top of the castle whenever you leave the island.
You can't costumize him in Astro Knights Island or Super Villain Island but you might search the common rooms for someone with his face.
Walk to the right.
its on top of the castle
There is no jail on Astro Knights Island. There is a castle dungeon, where an attacking alien robot is being held after his capture. (see the related question)
The Castle of ArturusThe castle is just to the right of Main StreetThe Castle of the Binary BardThe portal is on a large asteroid near X-11 Y-84 in the Asteroid Belt. To reach the castle, you will need all three knights so that you can use the Golden Key.
The royal castle of the Kingdom of Arturus is just to the right of the Main Street on Astro Knights island. (there is an intervening ad space) The castle of the Binary Bard is located on a giant asteroid in the asteroid belt (X-11 Y-82). You cannot go there until you have beaten all three planets in the solar system (Fire, Ice, and Jungle).
He says "bard".
There is a castle on Astro Knights Island, in the kingdom of Arturus.