Objective 1: Assemble the Lift
From the get-go, you’ve got company. If you’re looking to complete the Combat Challenge for the level, you have to work on completing it before anything else. Switch your character to Lex Luthor, then lure the enemies onto the cross-hatched zero-g pad area and quickly step onto the black and yellow pad to activate the zero gravity. While your foes are suspended in mid-air, target them with Lex Luthor’s blaster to make quick work of them.
Combat Challenge: Zero-G
Once the area is enemy-free, use Killer Croc to pull at the hyper strength handles of the craft on the right side of the zero-g pad. After you successfully rip them off, some bricks spill out onto the ground. Build these into a gravity turret. Use the gravity turret to move the three nearby LEGO objects into the gear assembly on the rear wall. Place the small gear into the right side, the large gear into the left, and the battery into the middle slot. This calls down the lift. Before stepping onto it, be sure to smash The Joker prop on the left side of the zero-g area.
The Joker Smash Challenge: 1 / 3
Objective 2: Arm the First Turret
After ascending to the second floor on the lift, you are assaulted by a group of goons. Deal with the baddies, then watch a particularly clumsy goon crash into the wall above the upper right platform. Head to the right and up the stairs. Destroy the surrounding props and build the LEGO bricks that you find there into a pump and a jack. Jump on the pump to raise the nearby door. You are now free to hack the computer terminal within.
After hacking the computer terminal, the gate below you opens. Head into the now-open door and make use of Robin’s Magnet Suit to rebuild the pump inside. Doing so completes the first turret. Switch to Killer Croc and dive into the pool below. Smash the submerged Joker prop, then rip the underwater gate off its hinges by using the hyper strength handles. Inside of the small alcove, you find The Joker Card.
The Joker Smash Challenge: 2 / 3
The Joker Card
Objective 3: Arm the Second Turret
Make your way to the stairs on the left side of the area. Some goons show up, but they shouldn’t be too much trouble—especially with Killer Croc on your team. After those baddies have been dealt with, take a dive into the pool where the LEGO bricks fell from the wall. Build these into hyper strength handles that attach themselves to the nearby underwater gate. Rip the gate from its hinges to expose some LEGO machinery. Smash it up to open the gate above, allowing you to access the pump made of blue magnetic LEGO bricks. Interact with the magnetic LEGO bricks to continue.
Don’t forget to head to the top level of the stairs where you find the final Joker prop to smash.
The Joker Smash Challenge: 3 / 3
Objective 4: Fire the Turrets
Ascend the ladder on the central platform and hack the computer terminal at the top. This causes the massive grappling hooks to fire and latch onto Brainiac’s craft, ending the level.