Rule out the usual hiding places first. If the piece really is gone, check the set piece by piece
and leave with the element ID LEGO asks for, or a link to buy the part.
Launcher, Large Figure Weapon Cannon, Midak Skyblaster with Black Housing [Complete Assembly]Pearl Light GrayPart 62233Element 4521177×1
Projectile, Large Figure Weapon, Zamor Sphere / BallPearl Light GrayPart 54821Element 4494056 or 4291759×4
Technic Axle and Pin Connector, Perpendicular with ExtensionPearl Light GrayPart 53586Element 4494486 or 4286268×2
Pearl Dark Gray
6 pieces
Large Figure Armor Panel / ShieldPearl Dark GrayPart 61805Element 4531173×1
Large Figure Head Barraki TakadoxPearl Dark GrayPart 57551Element 4531175×2
Large Figure Mask Avohkii (Post Karda Nui Exposure)Pearl Dark GrayPart 60921Element 4525730×1
Large Figure Skeletal, Limb, Lower Arm Section (Toa Pohatu)Pearl Dark GrayPart 60917Element 4531178×2
Trans-Neon Green
1 piece
Large Figure Head Connector Block Eye/Brain Stalk - ShortTrans-Neon GreenPart 57536Element 4505191×1
Tick each piece as you find it, or mark it missing.
When a piece really is missing
Ask LEGO
LEGO takes requests for pieces missing from a new set through its customer service site. The form asks for
the set number and each piece's element ID, the number printed beside the piece in the parts list at the back
of the instructions. This checker lists both.
Mark a piece missing and your list links it to an eBay search for that part, which also covers pieces from
older or second-hand sets.
Keep a record
Copy or download your missing list (the CSV opens in any spreadsheet), or print the whole checklist and tick
pieces off on paper. Your marks stay in this browser, so you can check a big set over several sittings.