Throw the Batarang at the red bulls eye target on the pipes. Switch to Robin and jump onto the suit signal to change into the Hazard Suit, then jump in the water in the middle of the room. Hold down the button to aim and aim at the fires to put them out. If you run out of water before all the fire is out, refill by jumping back into the water in the middle of the room.
Head right and down into the water, build a lever from the parts underwater and pull it to send Batman's suit signal up to him.
Switch to Batman and change into the Electric Suit at the Suit Signal. Head to the right, crossing the pipes that are crackling with electricity. Remove the electrical charge from the switch terminal. Switch back to Robin, and head to the right underwater, past the fan blade that has stopped spinning. Build rafts from the underwater parts as you continue to head to the right and pull the lever near the door to Killer Croc's room. Switch to Batman and jump across the rafts, then over the pipes, continuing to head to the right. Place the electric charge from the earlier
switch terminal into the one you find here to lure Killer Croc out of his room with food.
Switch to Robin and head to the right into the room vacated by Killer Croc. Break things for parts, build a lever, and pull it down to drain the water out of the room. If Batman doesn't automatically join Robin in the room, switch to him, head right, and jump down the hole to land in the room with Robin. Have Batman and Robin both turn the 2 wheels at the same time to open the path to the next area.
Head to the right and remove the electrical charge from the switch terminal using Batman's Electric Suit. Switch to Robin, break things for parts, build a suit signal and change out of the Hazard Suit back to Robin's default outfit. Then climb up the Acrobat Walls, head left, and repair the pipes with the parts lying on the floor. This will activate the lever near the entrance. Pull it down to freeze the waterfall. Switch to Batman, climb up the now frozen waterfall, and place the electrical charge from the lower switch terminal into the upper one, melting the ice on the ladder.
Climb up the ladder to the next area.
Red targeting cross hairs on the floor will show where Mr. Freeze is aiming his attacks, so avoid those spots while defeating his goons. Head to the left and remove the electrical charge from the switch terminal in the lower left corner, then place it into the switch terminal near the frozen wheel to defrost it. Head to the right and turn the wheel near the suit signal as well. This will knock Mr. Freeze down into the room where you can reach him. Defeat him, pick up the key card he drops and use it to access the suit signal in the corner. Change Robin into his Ice Suit, then freeze the
waterfall and climb up it. Head left and pull the lever down to make water spouts appear.
Freeze the two water spouts into ice pillars, then climb back up the frozen waterfall and jump across the top of the ice pillars following the trail of studs. Pull the lever to melt the ice blocking the path to the next area and proceed.
Head to the left and defeat the Mad Hatter's goons. You will not be able to reach the Mad Hatter himself, due to the Sonic Attack emitted by the grandfather clock pushing you back whenever you get near. Once all the goons have been defeated, parts for a suit signal will appear in the center of the room, and parts for a turn-wheel will appear in the far left corner. Build them, change Batman into his Sensor Suit, and use X-Ray Vision on the wall in the far left corner. Switch to Robin and turn the wheel to align the colored wires behind the wall, electrocuting the Mad Hatter.
Head back to the right, following the trail of studs up the stairs. Stealth past the security cameras. Do not waste time stopping to pick up studs if you miss any; just keep heading to the left as quickly as possible to avoid detection. Once you reach the computer terminal, hack into it and repeat the symbols it displays in the correct order to deactivate the security cameras. Head back to the door between the security cameras and have Batman and Robin pull both levers at the same time to open the door to the next area.
Head to the right, and stealth past the security camera. Go into the room with a tic-tac-toe game drawn on the back wall, and pull down the left wall of that room with grapple hook. Switch to Robin, join Batman in the tic-tac-toe room, break stuff for parts to build a suit signal and change into the Magnet Suit. Walk up the Magnetic Wall and pull the lever to deactivate the laser barrier. Switch to Batman, stealth past the next security camera as you head to the right, and hit the red bulls eye targets with a Batarang, holding down the button to select both targets with the targeting cursor before releasing the button. Go into the room that opens, pick up the toolbox and carry it out to the green circle on the floor. Assemble a lever from the parts that appear and pull it down to open another door. Switch to Robin, go into the room with the wooden crate, and press the buttom to climb inside it. While hidden inside the crate, head to the right past the security camera. Press the button to discard the crate after you are safely past the security camera, walk up the Magnetic
Wall and pull the lever to deactivate the laser barrier. Defeat the Asylum Inmates and hack into the computer to deactivate all the security cameras so you can head back to the left safely.
Head back to the left all the way to the far end where you first came in. Zsasz will walk into the room accompanied by 2 Asylum Inmates. Defeat them all (use the same strategy as for Catwoman when Zsasz stealths) pick up the key card, and use it to open the door to the next area.
Defeat the Scarecrow's goons as they appear. You can also break the pumpkins in the room for studs and/or hearts. When the Scarecrow makes the two giant needle traps start moving, red targeting cross hairs on the floor will show where the needles will strike. Avoid those spots, and attack the needles when their tips are stuck in the floor tiles. When both needles are defeated, the Scarecrow will make more goons appear and activate a chandelier trap. You can let the chandelier trap take out the goons if you want, continuing to avoid the red targeting cross hairs yourself. Hit the chandelier trap after it has closed but before it rises back up to the ceiling, to damage it. When the Scarecrow appears in the middle of the room, run over and hit him as many times as you can before he poofs again. The pumpkins, goons, and needle traps
will return so defeat them the same way as before. Scarecrow will also spawn some spiders half way through and the chandelier trap returns as well. You can either let the traps take out the spiders while you focus on hitting the traps or just attack everything yourself. When the scarecrow appears by the door, run over and finish him off. After the cut scene, Batman's Electric Suit and Robin's Ice Suit will be available at any time in Free Play Mode from now on.