Red bricks are items found in Lego games that give you access to different kinds of extras once found and purchased.

Unlike most Lego games where you simply find a hidden red brick in one of the main levels, Lego Avengers is a bit different. While playing each level in freeplay, someone known as the Collector can be found who will be wanting a certain item. Upon finding the item and giving it to him, you will be given the red brick.

Once you have a red brick, you can go to the Collector's room in the Helicarrier (when in the Helicarrier, go up the stairs to the left, then go in the first room to your right).

If you completed every story mission, you should have every type of character needed to obtain each red brick. However, you will still need two more:

• Ultron: Needed for dealing with cosmic bricks since he's the only character that can use them.
  
• Digging character: Needed to dig certain things up. I recommend getting Squirrel Girl (clear her mission found next to a tree on Barton's farm).

Red Brick: x2 Studs
Price: 1,000,000 studs
Location: Part B where Iron Man is flying around the building. Go through the vent on the left side as Vision. Activate the computer machine and solve the puzzle. Destroy everything in the garage to get Strucker's monocle. Get back to the main area and fly up to the top right to give it to the Collector.

Red Brick: x4 Studs
Price: 2,000,000 studs
Location: Part A when Loki first appears. Fly up to the right near the catwalk and mind control the guy so he can pull the switch. A mini rocket will appear. Give it to the collecter, who is at the very bottom left of the area down a ladder.

Red Brick: x6 Studs
Price: 4,000,000 studs
Location: Part B when you first start in the flashback. Activate the control panel in the middle of the room and mind control the guy so he'll pull the switch. Use Ultron's power on the box that appears and give the item to the Collector, who will be right next to you.

Red Brick: x8 Studs
Price: 6,000,000 studs
Location: Part B where you fight Loki in the city. The Collector is at the top left area and wants a hot dog. Go to the bottom right area to find a vendor and use mind control on the guy so he makes a hot dog for you. Give it to the Collector for the red brick.

Red Brick: x10 Studs
Price: 8,000,000 studs
Location: Part C at the start of the area. The Collector wants a baseball card, so use Ultron's power on the bricks next to him and rebuild the bricks to make a drone that will get the card for you. Give the Collector the card for the red brick.

Red Brick: Fast Fix
Price: 600,000 studs
Location: Part B where you're in the city streets. Fly up on the building in the front to find the Collector, who wants a wig. Go to the very bottom right area and use Scarlet Witch's power on a giant brick so the window in the shop breaks. Go in the shop, get the wig, and give it to the Collector.

Red Brick: Unlimited Avenger's Team-Up Moves
Price: 500,000 studs
Location: Part C when you're on Stark's tower. The Collector is standing outside and wants a computer object. Go inside of the building and use Ultron's pwoer on the elevator. The item will be behind the bricks, so go and give it to the Collector.

Red Brick: Character Token Detector
Price: 1,000,000 studs
Location: Part A when you're on the ship, near the end of the level. The Collector is at the top of the elevator and wants Arnim Zola's glasses. Fly up to the right and activate the S.H.I.E.L.D. terminal so the door opens (do not enter it!). Now activate the Hydra terminal and a laser will be activated which will destroy the structure to the right so the glasses appear, and give them to the Collector.

Red Brick: Gold Brick Detector
Price: 500,000 studs
Location: Part C just south of when you go up the elevator. He wants Iron Man's helmet, so fly up to the area above him and use a cloaking character like Black Widow to get past the camera. Blow up the silver object, build the switch, and pull it to open a new door. Melt the golden bricks and use Captain America's shields to get through the flames. Grab the helmet and give it to the Collector.

Red Brick: Minikit Detector
Price: 250,000 studs
Location: Part C at the bottom of the area. The Collector wants a teacup so use Scarlet Witch's power on the blue car to the right of him to find one for him.

Red Brick: Stan Lee in Peril Detector
Price: 300,000 studs
Location: Part B on the top right area (fly up to get there). The Collector wants some classical music, so go to the second floor and use Ultron's power on the turntable to find a classic record.

Red Brick: Quest Detector
Price: 1,000,000 studs
Location: Part A at the bottom left area of the main floor. The Collector wants some Vibranium, so blow up the metal door on the other side to get it for him.

Red Brick: Fast Build
Price: 500,000 studs
Location: Part C to the left of the crashed train. The Collector wants a fish, so go to the right and scan the vendor. A fish will appear but will then fall in some dirt, so dig it up with a character like Squirrel Girl and give the fish to the Collector.

Red Brick: Fast Dig
Price: 250,000 studs
Location: Part C at the very start of the area. The Collector wants a Sokovian flags, so scan the van he's standing next to and pull the green handles with someone strong like Hulk. Build the speed pad and use it with someone fast like Quicksilver to knock the flag down. Give it to the Collector.

Red Brick: Collect Ghost Studs
Price: 500,000 studs
Location: Part C in the second area after Scarlet Witch does her first attack. Dig through the ground to the right and put out the flames. Use telepathic powers on the crowbar, build the skeleton, and keep attacking it until it drops a skull. Give the skull to the Collector, who is right next to you.

If you followed this guide, you should now be able to purchase every red brick in the Collector's shop. Aside from the red bricks mentioned in this guide, you must also purchase the following red bricks which are available from the start:

• Attract studs (100,000 studs)
  
• Disguises (200,000 studs)
  
• Target second player (1,000,000 studs)

Now that you have every extra, make sure that they're all on at the same time so that you get the achievement.

I hope this guide helped in finding every red brick in the game. If you have any suggestions in making this guide better, please say so in the comments.