Each level in the "LEGO Batman" game contains 10 hidden canisters which, when collected, make up a mini-kit. This mini-kit unlocks something new for your game. The mini-kit you get from the Arctic World level unlocks a walrus. These canisters are scattered throughout the level, and while you can pick up some during the story mode, it's best to come back during a free play round and snag all 10 of them.
Begin or continue your "LEGO Batman" game and play through Level 5 of the Power-Crazed Penguin episode, entitled Arctic World. Complete the level once to unlock the level for free-play mode.
Begin Arctic World in free play mode.
Find the water suit and slip it on. Head out onto the frozen pond and break through the ice. Beneath the ice, you'll find a lever. Pull it to open the ice cream shop and reveal the first canister.
Find the sonic suit and put it on. Break the glass at the end of the floating platforms to get the second canister.
Double-jump up to the ski slope and blow up the shiny object at the top. Use a female villain on the heart panel to charm the ski lift attendant, who starts the ski lift. Use the Joker to grapple to the top of the slope and ski down. Pass through all of the gates to win the next canister.
Climb up the magnet wall next to the tourist centre. Rip the door off the generator, use the Joker to grapple onto the moving grapple point and ride it to the next LEGO canister.
Use the sonic suit to break all of the glass at the bar inside the tourist centre and a shark will appear to drop off your next canister.
Go into the puddle of toxic goo inside the tourist centre. Pull out the handle block and drop it on one of the buttons. Direct your other characters to stand on the other buttons to reveal the next canister.
Go down the ice slide and pass through the five gates to get the next canister. The best way to do this is stick to the right for the first two gates, then switch characters and grab the third gate to the far left. This is a challenging manoeuvre, because if you miss it on this pass-through, you will have to replay the level to try this part again.
Enter the last zone and blow up the shiny metal grate. Use the parts to assemble a trampoline and jump up to catch the next canister.
Look for a cage containing a canister suspended above you. Use Mr. Freeze to ice up the water in the pond to the right and use the frozen blocks to reach the cage. Double-jump up and break the cage to free the part.
Dive into the water while wearing the water suit to find a huge hunk of ice. Swim under that ice to find the last of the canisters.
Return to the main menu and find the mini-kit located inside the Arkham Asylum trophy room. Assemble the mini-kit and collect your reward.