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.
523 pieces in 143 part and color combinations, plus 12 minifigures.
LEGO counts 588 pieces. This inventory comes from a separate parts catalog and lists 590, including the 67 parts inside the minifigures; the two do not always count the same elements, so their totals differ. 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.
Technic Axle Pin without Friction Ridges LengthwiseLight GrayPart 3749Element 4184168 or 4154179×1
Technic Pin 1/2 without Friction RidgesLight GrayPart 4274Element 427402×1
Baseplates
1 piece
Baseplate Raised 32 x 32 with Ramp and Pit, Rocks Light and Dark Gray PrintGreenPart 2552pr0004×1
Plates Wedged
1 piece
Wedge Plate 3 x 3 Cut CornerLight GrayPart 2450Element 245002×1
Tiles
1 piece
Tile 1 x 1 with GrooveBlackPart 3070bElement 307026×1
Wheels and Tyres
1 piece
Technic Wedge Belt Wheel [aka Pulley]BrownPart 4185Element 4162482 or 4107463×1
Minifigures
12 figures
Knight (Scale Mail on Red) - Black Arms, Black Legs, Black Neck-ProtectorMinifigure, checked as a whole figure×1
Ghost - Glow in the Dark, Brick Built Legs, 3626bMinifigure, checked as a whole figure×1
Knight (Scale Mail on Red) - Black Arms, Black Legs, Black Neck-Protector, Plastic CapeMinifigure, checked as a whole figure×1
Knight (Breastplate on Red) - Red Legs, Blue Dragon PlumeMinifigure, checked as a whole figure×1
Knight (Breastplate on Blue) - White Legs, White Dragon PlumeMinifigure, checked as a whole figure×1
Knight (Breastplate on Blue) - Black Legs, Red Dragon PlumeMinifigure, checked as a whole figure×1
Knight (Breastplate on Black) - Black Legs, Armor, Yellow Dragon PlumeMinifigure, checked as a whole figure×1
Archer (Scale Mail on Red) - Black Arms, Red LegsMinifigure, checked as a whole figure×1
Archer (Scale Mail on Red) - Blue Arms, Blue LegsMinifigure, checked as a whole figure×2
Archer (Scale Mail on Red) - Blue Arms, Red LegsMinifigure, checked as a whole figure×1
Fighter (Wolfpack) - Brown HoodMinifigure, checked as a whole figure×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.