Chapter 5: Chemical Crisis
Be careful of the toxic sludges as you'll lose hearts by getting in contact with them. First, destroy the lego blocks to the right of the cylinder containing the hazard suit. Reassemble it to become a switch and to open the cylinder. Switch to Robin's suit and head to the water tank further to the right. Activate the switch.
Jump up and examine the canister to get the first chemical vial. The path leading to the next area should open. Continue along the walkway until you reach the area where the lift gets blown off by the Joker's trap. First, destroy all the shining “locks” then activate the terminal. Next, clean the green slude by blowing it with the Hazard Suit's water cannon. This will enable you to change into Batman's Electricity Suit.
Go up the ladder and turn off the electricity using the switch. Go to the left until you reach another chemical vial. Defeat the goons and switch the Robin. Jump to the water tank and continue to the right. Activate the terminal there.
Continue to the right and clean the slude. Reassemble the blocks to change into Robin's Magnet Suit. Continue to the upper level and pull the blue cone. Power it up using Batman's Electricity Suit then examine the red canister to get the red chemical vial.
Continue forth and reassemble the bridge pieces so you have something to jump on. Continue to the right and ride and hop the moving barrels until you reach the other platform. Pull the blue barrels north then access the orange chemical canister.
Jump on the barrels again to proceed to the right. Have Batman drain the electricity so Robin can change to his Hazard Suit. Jump on the colored liquids to refill your tank then aim and shoot the liquid in the corresponding hole. Fill all three tanks to clean the green chemical vat to the right.
Have Batman reach the other side first then drain the electricity then switch to Robin and clean the sludge so you can access the terminal. Defeat the goons and have Batman turn off the terminal to the right first. Next, regroup with Robin and use the forklift to reach the other terminal. Turn it off as well.
Have Robin jump inside the large tank and access the terminal in the upper part of it. This should drain the water. Examine the canister to get the last chemical battle.
After the checkpoint, clean up the sludge. Your current water supply won't be enough so you have to assemble the broken lego pieces to the left so the water pit gets refilled. Put out the fire and reassemble the pieces to change into Robin's Acrobat Suit.
Switch to the other side and have Robin operate the machine using his Gyroball ability. After Batman crosses, drain the electricity from the leftmost outlet then power up the second. Reassemble the pieces to reveal Batman's Power Suit.
Continue to the right and open the barricade. Destroy the silver parts and climb the blue pole. Reassemble the pieces to form a grappling handle. Have Batman remove the barricade again then have Robin make his way up. Hit the nearby ladder so Batman can go up as well. Destroy the silver parts to create a footbridge for you to reach the other side.
Continue to the right and destroy the two large computer panels beside the large screen. Reassemble the pieces to complete the gyro ball mechanism. Have Robin operate it then move the cursor to turn off both ice jets. Proceed to the right then remove the barricade so Robin can operate the gyro ball mechanism above.
Move the platform towards Batman first so he can ride, then move it to the right so he can change back into his Electricity Suit. Drain the power then continue to the right. Once the gate is opened, have Robin move across the toxic vats and deactivate the terminal. Have Batman recharge the next power outlet then jump on the large metal box to reach the next checkpoint.
Superman will now join the party. Take this time to familiarize with his controls. First, use your freeze breath to take out the fire. (1/5) Next, fly up then pull the orange handle to the left. Once the fire is extinguished, use his Freeze Breath so Batman and Robin can follow suit.
Along the catwalk, extinguish the small fire again (2/5) then reassemble the pieces so Batman can change to his Power Suit. Blow up the silver barrier nearby so Robin can change to his Hazard Suit. Continue to the right and have Superman use his X-Ray vision to operate the handles behind the blue wall. This should open the valves nearby.
Proceed to where the chemical/ water pits are. Extinguish the small fire again (3/5) then use Superman's heat ray vision to destroy the gold objects. Have Robin step on the orange pit and fill the orange hole with liquid. Find the other colored vats and fill the corresponding valves.
Change Batman back to his Electricity Suit then have Superman freeze the water fountains. Drain the electricity then let Superman fly up. Have him cut through the solid surface of the water tank to extinguish the large flames below. To the right of the water tank is a small fire as well. (4/5)
Proceed to the next tank and do the same. This time, freeze the water so Batman and Robin have something to grab unto. Continue to the far right until you find the last fire to douse. This should reveal a mini-kit. Power up the lift then continue to the next checkpoint.
You should change into the Power Suit however, you won't be able to do that immediately. For now, have Superman destroy the two gold objects here. (2/5) There is another one above so fly up and you should find it ton the wall. (3/5) Have Superman fly to the other side and destroy the remaining two golden cabinets. You'll get another mini-kit here.
Have Batman cross the electric field then let Superman destroy the golden blocks and reassemble the ladder. Use Batman to discharge the electricity then have him change to his Power Suit. Backtrack to the right and destroy the support beams to complete the stage.