Batcave Trophies, Red Bricks, Riddler Puzzle Boxes, Poison Ivy Plants, Cluemaster puzzle boxes, mini kits — there are many collectibles to be found throughout Lego Batman: Legacy of the Dark Knightto say the least, and while most are fairly easy to find, thanks to the radio towers, there is one unmarked collectible that doesn't show up on the checklists.
The Bat Symbols are glowing coins with Batman's logo on them, and you can find them scattered all over Gotham City. Since they aren't visible on the map, they're a little hard to spot, and your detective vision won't be of much use here. But don't worry, we've spent hours mindlessly sliding across the map to reveal them so you don't have to.
This guide is a work in progress and we are currently missing seven bat symbols.
East End – Amusement Mile
Gotham Village – Robinson Park
Newtown
Old Gotham North
Old Gotham South
Old Gotham West
The Cauldron North – Ace Chemicals
The cauldron south
Tricorner
Reward for unlocking all Bat symbols
When you collect bat symbols, a giant T-rex will begin to form in the Batcave; this appears to be a reference to the mechanical dinosaur from Batman #35 that was given to Batman as a memento for defying Murray Hart's Dinosaur Island theme park.
Once you've done that collected 25 of the bat symbolsyou will also be rewarded the trophy/achievement “The idea was to be a symbol”..

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