Full list of all 71 LEGO Worlds achievements worth 1,345 gamerscore. It takes around 50-60 hours to unlock all of the achievements in the base game on Xbox One.
The base game contains 61 achievements worth 1,000 Gamerscore, and there are 2 DLC packs containing 10 achievements worth 345 Gamerscore.
Found all the Biomes
Found the Legendary 1x2 Brick
Collected all the brick elements
Played bagpipes to a brown bull
Found the Legendary 1x1 Brick
Splatted a seagull with a paint-ball gun, while it was in mid-flight
Rode 4 different creatures within 60 seconds
Found the Legendary 1x3 Slope Brick
Played the trumpet to an Elephant
Achieved 5 consecutive seconds of vehicle air time (not including off the edge of the world)
Collected 100 Gold Bricks
Found and walked around a Town
Chased down and rode a Sheep
Dived continually for 3+ minutes
Rode a Badger
Had 5 squirrels following you around at the same time
Collected 60,000+ studs in a single streak (no more than 2 seconds between each stud collected)
Defeated 7 enemies in a streak (with a maximum 12 second gap in between)
Found a Dungeon
Rode a Shark on land
Collected 80 Gold Bricks
Collected 65 Gold Bricks
Collected 50 Gold Bricks
Collected 40 Gold Bricks
Collected 30 Gold Bricks
Collected 25 Gold Bricks
Collected 20 Gold Bricks
Took a picture of a posing character
Collected 15 Gold Bricks
Had two tamed pets following at the same time
Chased down and rode a Pig
Completed 15 seconds of consecutive climbing, jumping or back-flipping
Found an item in a chest
Bought something from the night Trader
Caught a Troublemaker
Completed the Candy Construction Capers World
Collected 10 Gold Bricks
Completed the Prehistoric Peril World
Completed the Pirate Playground World
Collected 3 Gold Bricks
Started your Adventure
Use the terraforming abilities of all capable vehicles
Accumulate 10+ seconds of consecutive zip time with the grapple gun in one grapple session
Skydive uninterrupted from the highest point possible to the lowest point possible!
Play an instrument next to another player, who's playing a different instrument
Blow up another player with a ridden Dragon fire ball
Find the Legendary 2x2 Brick
Find the Legendary 2x3 Brick
Find the Legendary 2x4 Brick
Find the Legendary 1x2 Slope Brick
Find the Legendary 2x2 Slope Brick
Find the Legendary 2x3 Slope Brick
Find the Legendary 1x4 Slope Brick
Find the Legendary 2x4 Slope Brick
Find the Legendary 1x2x3 Slope Brick
Find the Legendary 2x2x3 Slope Brick
Find the Legendary 2x2 Corner Brick
Find the Legendary 3x3 Corner Brick
Bounce on Lava 7 times consecutively
Play all the musical note bricks within 10 seconds
Collect a billion studs
Defeated 8 Large Space Spiders within 40 seconds
Driving the Space Buggy, launch it into the air for 3 seconds
Play some lunar tunes on the moon with another player whilst using a different musical instrument
Take Intergalactic Girl to the Classic Space Biome (Moonwalking optional!)
Shoot 10 rockets from the mobile Rocket Launcher
Played a guitar solo in the Monster Biome stage area in front of the crowd
Create a single custom character, using a part from each of the new monster characters
Stake a claim to Monster Town by playing as the classic Vampire character in the Monsters pack
Use the paintball gun to splatter paint on all the new monster characters
Collect Vampire & Lord Vampyre's Bride, then place them together in the Monsters castle