Hall of Justice
Note: The totals for collectibles in this hub include the Hall of Doom.
Gold Brick #1
Head right from the entrance to find a little spaceship ride. Hop in for a few seconds to win a Gold Brick.
Gold Brick #2
There are six gold statues in the room to melt with a laser character. Check on all three levels on either side for all six, and you'll earn a brick for it.
Gold Brick #3
You'll find Dex-Starr on the top left floor. Talk to him and beat up the goons that appear to finish the quest.
Gold Brick #4
Supergirl and Superboy are hanging out on the top floor, right side. They only let "super" people into their club, so make a custom character with Superman's torso and return to them to finish this quick quest.
Gold Brick #5
Return to the hall and speak to Supergirl to learn that some people are in danger. The first two are stuck in the nearby fountains; use a frost character to save them. Next, check the second floor, left side to find Superboy stuck under some Flash statues. Pull them away with a magnetic character, then head to the second floor, right side for the last trapped tourist. To free him from the cabinet, use a tech character on the panel on the ground floor to release the proper lock. After all this, you'll be given a Gold Brick.
Gold Brick #6
You can find Kevin Smith by the teleporter, needing help on his documentary. To do so, you'll need to disable eight traps around the ground floor. There are two gold yoyos to melt with a laser character, three Joker boxes with targets to shoot and build back into locks, and three bear traps to grapple shut. Disable all of these to earn a brick.
Gold Brick #7
Near the right fountain is Batgirl. Talk to her to learn of some tourists under the Mad Hatter's control. To save them, head to the second floor, right side and knock the hats off of each of them with a punch. Return to Batgirl with them to finish the quest.
Gold Brick #8
You can find Nightwing by the left fountain; he needs your help getting over his fear of circuses. To do this, you need to use an acrobatic character to navigate the series of platforms, jumping through each ring before time runs out. Make it through the whole course for a Gold Brick.
Gold Brick #9
Gold Brick #10
Finally, the Riddler will appear on the left side of the ground floor, taunting you with - of course - a riddle. To solve it, you first need to watch which box the handle lands in and step on the correct colour. Grapple the hook out of the box to move on. In the second round, you need to press three switches, a tricky task for two characters. I solved it by simply running across all three with a fast character. In the final round, you need to press the switches so that the box fronts match the colours hanging from the lights. After all this, you'll earn your Gold Brick.