UPDATE: Thanks to
Seeker74Be sure you go to all 7, one after the other. The game does not keep track of where you have been over the course of the game.
Posted by Seeker74 on 30 Nov at 3:30 pm
You can get this when you go to the moon in the base you will see the 6 doors to each of the lantern planets you will need to build the door using a fast character such as superman or the flash builds the doors quick all you need to do is go in and out of each of the doors in the moon base and the last one is oa green lanterns its directly behind the entrance / exit a big green door (need to build) as soon as you enter the last one achievement pops.
***note: You may need to beat the campaign past a certain level ie; to unlock the respective planets this will not be obtainable from the start of the game.
To rebuild every door you will need
40 Gold Bricks in total.
*****Extra note: There are 3 achievements that you can get in the moon in one go (given how far you have progressed in the story.) Links are below for the achievements with video guides
--- two are listed here the only one not listed on the video below is the hey diddle diddle achievement.
Video included for locations.
I included where to go to the moon which also is an achievement
One Small Step for (Bat)Man... (20)
Visit the Moon Base in the Hub
You need to talk to green loontern (daffy duck) he is located where the batman info signal is right outside the door to the moon base (the end of the video)
2 Achievements in one!