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LEGO Missing Piece Checker

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.

Sea Serpent

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40912 Sea Serpent

233 pieces in 92 part and color combinations, plus 2 minifigures.

The official piece count includes the 8 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.

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.

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Piece checklist

Reddish Brown 71 pieces

  • Antenna 1 x 4 with Flat Top Reddish Brown Part 3957b Element 4538252 ×4
  • Bar 1L with Clip [Cut Edges and One Side Hole] [Full Clip] Reddish Brown Part 3484 Element 6439053 ×4
  • Bracket 1 x 1 - 1 x 1 Inverted Reddish Brown Part 36840 Element 6238874 ×6
  • Bracket 1 x 1 - 1 x 2 Reddish Brown Part 79389 Element 6472546 ×2
  • Bracket 1 x 1 - 1 x 2 Inverted Reddish Brown Part 73825 Element 6341553 ×10
  • Bracket 1 x 2 - 1 x 2 Inverted Reddish Brown Part 99780 Element 6174856 ×2
  • Cone 1 x 1 [Top Groove] Reddish Brown Part 59900 Element 4529242 ×2
  • Equipment Oar / Paddle [Reinforced] Reddish Brown Part 87585 Element 4609635 ×2
  • Large Figure Weapon Lightsaber Hilt with Axle Hole and Two Bar Holders Reddish Brown Part 24122 Element 6459423 ×2
  • Plate 1 x 4 Reddish Brown Part 3710 Element 4211190 ×2
  • Plate 2 x 3 Reddish Brown Part 3021 Element 4211189 ×4
  • Plate 2 x 4 Reddish Brown Part 3020 Element 4211186 ×2
  • Plate 2 x 6 Reddish Brown Part 3795 Element 4211247 ×1
  • Plate 4 x 6 Reddish Brown Part 3032 Element 4271874 or 4211213 ×1
  • Plate Special 1 x 2 with Bar Up [Horizontal Arm 5mm] Reddish Brown Part 88072 Element 6261359 or 6173941 ×1
  • Plate Special 2 x 2 with Groove and Center Stud (Jumper) Reddish Brown Part 87580 Element 4565394 ×2
  • Technic Axle Connector Smooth [with x Hole + Orientation] Reddish Brown Part 59443 Element 4531751 ×2
  • Technic Pin Connector Round [Slotted] Reddish Brown Part 62462 Element 6173132 or 6055781 ×3
  • Tile 2 x 4 with Groove Reddish Brown Part 87079 Element 4579690 ×1
  • Tile Round 1 x 1 Reddish Brown Part 98138 Element 6284586 or 6133854 1 spare in the box ×1
  • Tile Round 1 x 1 Quarter Reddish Brown Part 25269 Element 6149677 1 spare in the box ×2
  • Wedge Plate 2 x 2 Left Reddish Brown Part 24299 Element 6385263 ×2
  • Wedge Plate 2 x 2 Right Reddish Brown Part 24307 Element 6385262 ×2
  • Wedge Plate 4 x 2 Left Reddish Brown Part 41770 Element 4205470 ×2
  • Wedge Plate 4 x 2 Right Reddish Brown Part 41769 Element 4205469 ×2
  • Wedge Plate 6 x 3 Left Reddish Brown Part 54384 Element 6503730 ×2
  • Wedge Plate 6 x 3 Right Reddish Brown Part 54383 Element 6503731 ×2
  • Window 1 x 2 x 2 Castle Reddish Brown Part 90195 Element 6063447 ×3

Black 61 pieces

  • Brick Arch 1 x 6 Raised Arch Black Part 92950 Element 4620763 ×1
  • Brick Curved 2 x 1 with Inverted Cutout Black Part 78666 Element 6369578 ×2
  • Brick Curved 4 x 1 Double, No Studs Black Part 93273 Element 4613153 ×2
  • Brick Round 1 x 1 Open Stud Black Part 3062b Element 306226 ×2
  • Brick Round, Curved 10 x 2 x 2 with Rounded End Left Black Part 77180 Element 6523486 or 6476044 ×2
  • Brick Round, Curved 10 x 2 x 2 with Rounded End Right Black Part 77182 Element 6523487 or 6465736 ×2
  • Brick Sloped 45° 2 x 2 Black Part 3039 Element 303926 ×1
  • Brick Special 1 x 1 x 1 2/3 with Studs on 1 Side Black Part 32952 Element 6228987 Also in Dark Bluish Gray ×6
  • Brick Special 1 x 2 Palisade [aka Log] Black Part 30136 Element 4644456 or 4519980 ×2
  • Brick Special 1 x 2 x 1 2/3 with 8 Studs on 3 Sides Black Part 67329 Element 6308883 ×2
  • Hinge Brick 1 x 2 Base Black Part 3937 Element 393726 ×1
  • Hinge Brick 2 x 2 Top Plate Thin Black Part 6134 Element 4124096 or 613426 ×1
  • Hinge Plate 1 x 4 Swivel Top / Base - Hollow Clip [Complete Assembly] Black Part 1927 Element 6672302 or 6416444 ×4
  • Plate 1 x 2 Black Part 3023 Element 302326 ×5
  • Plate 1 x 4 Black Part 3710 Element 371026 ×3
  • Plate 2 x 3 Black Part 3021 Element 302126 ×2
  • Plate Special 1 x 2 Rounded with 2 Open Studs Black Part 35480 Element 6210270 ×13
  • Plate Special 1 x 2 [Side Handle Closed Ends] Black Part 48336 Element 4225201 ×1
  • Plate Special 1 x 2 with Clips Horizontal [Open O Clips] Black Part 60470b Element 6310268 or 4556158 ×1
  • Plate Special 2 x 2 x 2/3 with Axle Hole and Grill on Sides (Haybale) Black Part 71752 Element 6325254 ×1
  • Technic Axle 10 Black Part 3737 Element 373726 ×1
  • Technic Bush 1/2 Smooth with Axle Hole Semi-Reduced Black Part 32123b Element 6600750 1 spare in the box ×1
  • Tile Special 2 x 2 with Top Pin [Squared Holes] Black Part 49153 Element 6313191 ×1
  • Tile Special Round 2 x 2 with Hole Black Part 15535 Element 6143850 ×1
  • Weapon Lightsaber Hilt with Bottom Ring Black Part 64567 Element 4614712 or 4598897 1 spare in the box ×2
  • Wedge Plate 2 x 4 Black Part 51739 Element 4531412 ×1

Blue 28 pieces

  • Plate Special 1 x 1 x 2/3 Half Round with Side Stud Blue Part 3386 Element 6482573 ×8
  • Technic Axle Pin with Friction Ridges Lengthwise Blue Part 43093 Element 4309323 or 4206482 ×4
  • Tile 1 x 2 with Groove Blue Part 3069b Element 306923 ×2
  • Tile 1 x 8 with Groove Blue Part 4162 Element 416223 ×2
  • Tile 2 x 2 Corner Blue Part 14719 Element 6129747 ×10
  • Wedge Plate 3 x 2 Left Blue Part 43723 Element 4498156 or 4280150 ×1
  • Wedge Plate 3 x 2 Right Blue Part 43722 Element 4498155 or 4280149 ×1

Pearl Gold 17 pieces

  • Equipment Goblet / Glass Pearl Gold Part 2343 Element 4505990 ×1
  • Flag 4 x 1 Wavy [First Wave Right] Pearl Gold Part 4495b Element 6268949 or 4504649 ×2
  • Plate Round 1 x 1 with Solid Stud Pearl Gold Part 6141 Element 4523159 1 spare in the box ×8
  • Tile Round 1 x 1 with Golden Crown Print Pearl Gold Part 98138pr0283 Element 6375358 1 spare in the box ×1
  • Tile Special 1 x 2 with Sloped Walls AKA Money / Gold Bar [Ingot] Pearl Gold Part 99563 Element 6207933 or 4651407 ×2
  • Window Pane Latticed 1 x 2 x 2 Pearl Gold Part 38320 Element 6477142 or 6295686 1 spare in the box ×3

Light Bluish Gray 13 pieces

  • Plate Special 1 x 1 x 2/3 Half Round with Side Stud Light Bluish Gray Part 3386 Element 6448793 ×6
  • Plate Special 2 x 2 x 2/3 with Two Studs On Side and Two Raised [Half Hollow Anti-stud] - Updated Version Light Bluish Gray Part 4304 Element 6469440 ×6
  • Tile 2 x 3 Light Bluish Gray Part 26603 Element 6171894 ×1

White 10 pieces

  • Bar 3L White Part 87994 Element 6552205 or 6428803 1 spare in the box ×1
  • Brick Special 1 x 2 x 1 2/3 with 4 Studs on 1 Side White Part 22885 Element 6603759 or 6218823 ×4
  • Plate 1 x 2 White Part 3023 Element 6552100 or 6548261 ×2
  • Plate 2 x 4 White Part 3020 Element 6552098 or 302001 ×2
  • Sail, 9 x 12 with 4 Holes in White with Red Griffin Print White Part 118832 Element 6618122 ×1

Dark Bluish Gray 9 pieces

  • Brick Special 1 x 1 x 1 2/3 with Studs on 1 Side Dark Bluish Gray Part 32952 Element 6228923 Also in Black ×6
  • Plate Special 2 x 2 with Groove and Center Stud (Jumper) Dark Bluish Gray Part 87580 Element 6126083 or 4565322 ×1
  • Technic Pin 1/2 with Friction Dark Bluish Gray Part 89678 Element 6395635 1 spare in the box ×1
  • Tile 1 x 2 with Groove Dark Bluish Gray Part 3069b Element 4211052 ×1

Dark Brown 8 pieces

  • Barrel 2 x 2 x 2 Dark Brown Part 2489 Element 6605459 or 6278987 ×1
  • Brick Sloped 18° 2 x 1 x 2/3 Dark Brown Part 5404 Element 6509391 ×6
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) Dark Brown Part 4032a Element 4623298 ×1

Flat Silver 5 pieces

  • Shield Triangular with Spiked Top with Red/Blue Griffin on Yellow Background Print Flat Silver Part 4972pr0005 Element 6627638 ×2
  • Weapon Axe Head, Clip-on (Viking) [Thick Clip] Flat Silver Part 53454 Element 6363145 or 6292957 ×1
  • Weapon Pike / Spear Flat End Flat Silver Part 93789 Element 4611883 ×1
  • Weapon Sword with Thick Crossguard (Roman Gladius) Flat Silver Part 18034 Element 6093532 1 spare in the box ×1

Red 5 pieces

  • Brick Curved 1 x 2 x 1 2/3 with 1 Cutout Red Part 5907 Element 6547136 ×4
  • Plate 2 x 16 Red Part 4282 Element 428221 ×1

Medium Nougat 3 pieces

  • Container Box 2 x 2 x 1 Reinforced Bottom Medium Nougat Part 2821 Element 6435640 ×2
  • Tile Round 1 x 1 with Cookie Print Medium Nougat Part 98138pr0018 Element 6287854 or 6055384 1 spare in the box ×1

Tan 2 pieces

  • Plate 1 x 6 Tan Part 3666 Element 4124067 or 366605 ×2

Dark Blue 1 piece

  • Flag 4 x 1 Wavy [First Wave Right] Dark Blue Part 4495b Element 6268948 or 4504647 ×1

Minifigures 2 figures

  • Griffin Knight, Female, Dark Blue Arms Minifigure, checked as a whole figure ×1
  • Griffin Knight, Male, Dark Blue Arms Minifigure, 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.

Request a replacement from LEGO

Buy the piece

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.

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