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.
Weapon Spike Flexible 3.5LRedPart 64727Element 6270082 or 4616842×2
Pearl Titanium
3 pieces
Large Figure Weapon Claw, HalfPearl TitaniumPart 92217Element 4612489×2
Large Figure Weapon, Zamor Sphere Launcher, Top with Barrel and SightPearl TitaniumPart 98563Element 4652055×1
Bright Green
1 piece
Projectile, Large Figure Weapon, Zamor Sphere / BallBright GreenPart 54821×1
Light Bluish Gray
1 piece
Technic Pin 1/2 without Friction RidgesLight Bluish GrayPart 4274Element 4274194 or 42114831 spare in the box×1
Trans-Neon Orange
1 piece
Large Figure Head Connector Block (Glatorian)Trans-Neon OrangePart 64262Element 4543426 or 4540702×1
White
1 piece
Large Figure Chest Badge with 'H' Hero Factory Logo on Light Bluish Gray Background PatternWhitePart 98570pat0001Element 6048911 or 6000987×1
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.