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.
291 pieces in 137 part and color combinations, plus 2 minifigures.
LEGO counts 293 pieces. This inventory comes from a separate parts catalog and lists 300, including the 9 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.
Look-alike colors in this set
These parts appear in this set in two colors that are easy to confuse. If you are one short in one color,
check whether it went in where the other color belongs. Each color has its own element ID in the parts list
at the back of the instructions.
Cone 1 x 1 [No Top Groove]Yellow ×2Trans-Yellow ×2Trans-Yellow is see-through: hold the piece up to a light.
Plate Round 1 x 1 with Solid StudPearl Light GrayPart 6141Element 42604781 spare in the box×8
Trans-Neon Green
6 pieces
Brick Round 2 x 2 x 1 2/3 Dome Top, Blocked Open StudTrans-Neon GreenPart 30151aElement 4506533 or 4144475×6
Green
4 pieces
Cone 1 x 1 [No Top Groove]GreenPart 4589Element 4188820 or 458928×4
Yellow
4 pieces
Cone 1 x 1 [No Top Groove]YellowPart 4589Element 458924Also in Trans-Yellow×2
Plate 2 x 3YellowPart 3021Element 302124×1
Technic Beam 1 x 2 ThickYellowPart 43857Element 4187122×1
Tan
3 pieces
Technic Axle Pin without Friction Ridges LengthwiseTanPart 3749Element 4666579 or 4186017×3
White
3 pieces
Panel 1 x 2 x 1 [Square Corners]WhitePart 4865aElement 486501×2
Wheel Centre Small with Stub Axles (Pulley Wheel)WhitePart 3464Element 4296997×1
Orange
2 pieces
Minifig Head Pumpkin, Evil Grin Print [Blocked Open Stud]OrangePart 3626bpr0507Element 4511895×2
Pearl Gold
2 pieces
Tile Special 1 x 2 Grille with Bottom GroovePearl GoldPart 2412bElement 4490599×2
Trans-Yellow
2 pieces
Cone 1 x 1 [No Top Groove]Trans-YellowPart 4589Element 6188441 spare in the boxAlso in Yellow×2
Trans-Brown
1 piece
Windscreen 7 x 4 x 1 2/3 with HingesTrans-BrownPart 30372Element 4193545 or 4124122×1
Trans-Clear
1 piece
Brick 1 x 2 without Bottom TubeTrans-ClearPart 3065Element 6514262 or 6244904×1
Trans-Green
1 piece
Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope)Trans-GreenPart 54200Element 6245270 or 4244573×1
Trans-Red
1 piece
Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope)Trans-RedPart 54200Element 6245252 or 4244363×1
[No Color/Any Color]
1 piece
Sticker Sheet for Set 7786-1[No Color/Any Color]Part 60400Element 4511970×1
Minifigures
2 figures
Batman, Light Bluish Gray Suit, Dark Blue Cape and CowlMinifigure, checked as a whole figure×1
Scarecrow with Glow in the Dark Head and Black HatMinifigure, 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.