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.
228 pieces in 91 part and color combinations, plus 3 minifigures.
The official piece count includes the 17 parts inside the set's minifigures, which this inventory lists separately. Spare parts are counted in neither figure.
Before you call it missing
Builders who report a missing piece often find it in one of these places. Tick each one off as you look.
Plate 1 x 4Reddish OrangePart 3710Element 6469089×2
Plate 1 x 6Reddish OrangePart 3666Element 6469087×1
Tile 2 x 2 Curved, MacaroniReddish OrangePart 27925Element 6475326×2
Blue
2 pieces
Technic Pin Long with Friction Ridges Lengthwise, 1 Center SlotBluePart 42924Element 6299413×2
Trans-Clear
2 pieces
Bar Curved with Axle End and 1 x 1 Round PlateTrans-ClearPart 4042Element 6510119 or 6444527×1
Dish 3 x 3 Inverted [Radar]Trans-ClearPart 43898Element 6507917 or 6244730×1
Trans-Light Blue
2 pieces
Cone 1 x 1 [Top Groove]Trans-Light BluePart 59900Element 6514027 or 6337639×1
Wave / Lightning with Axle HoleTrans-Light BluePart 2149Element 6508017 or 6420236×1
[No Color/Any Color]
1 piece
Sticker Sheet for Set 76289-1[No Color/Any Color]Part 10108779Element 6488180×1
Minifigures
3 figures
Thor, Rubber CapeMinifigure, checked as a whole figure×1
Fire DemonMinifigure, checked as a whole figure×2
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.