As Merlin the owl, fly down to pick up the bombs Mordred drops, and fly above his head. When the bomb flashes red, drop it on the green ball on his head.
Mordred will zap the owl leaving you to beat him, and the princess will say jump up the robot to reach me. Duck down and let the robot roll over you. Climb up it to jump to the platform, then to one of the chandeliers. When Mordred shoots a laser at you, the chandelier will drop and hit him. Do the same with the other chandelier and you've beaten him.
Tip: when jumping to the chandeliers let him try to shoot at you before you jump, then jump so he moves right under the chandelier to shoot again.
There are no cubes on Astro Knights island. There are ice floes on the Ice Planet, that you jump across to avoid the robot fish.
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)
Actually, Merlin has little to do on Astro Knights Island. He recovers the fuel rod from the dungeon when the robot self-destructs. And he battles Mordred at the very end of the island.
you fight the robot on jungle planet
One of the robot attackers was captured and put in the castle dungeon.
Things that Zap you on Poptropica : Lasers (Spy Island) Electrified Windows (Spy Island) Mini-Bots (Spy Island) Electric Fence (Diamond Mine, Nabooti Island) Electric Caterpillars (Jungle Planet, Astro Knights Island) Mordred's Robot (Astro Knights Island)
When you awaken the robot owl Merlin, he flies out of Mordred's lab. In order to get him back, you have to feed him the robot mouse. (chomp)
Throw the switch when you get the cheese. You can enter the dungeon from Mordred's underground laboratory once you have the robot owl. (see the related question)
There doesn't seem to be a drain there. There's a robot owl, who will follow you if you feed him a mouse. There's a dirt wall you can push through, and a tunnel to the dungeon where the robot attacker is kept. The gate at the end is opened from the library entrance to the dungeon.
Feed the robot mouse to the owl, and then he will follow you. In the dungeon cell, click the owl, then the fuel rod, and he will retrieve it for you. (see related question)
In the Maid's room (castle first floor left), feed the cheese to the robot mouse.
Go to Mordred's tunnel and you'll see the robot. Get the fuel rod and then go to the ship. From then on, you'll be in SPACE!