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40912 LEGO Ideas Sea Serpent thumbnail image

40912 LEGO Ideas Sea Serpent
Images 5Description 
40912 LEGO Ideas Sea Serpent
  • Sea Serpent thumbnail
  • Sea Serpent thumbnail
  • Sea Serpent thumbnail
  • Sea Serpent thumbnail
  • Sea Serpent thumbnail

LEGO 40912 Sea Serpent is a Ideas set currently valued at $45 for new and sealed sets. The set retired in July 2026 with annual appreciation averaging 18.74% since. On the used market, values range from $37 to $46 based on condition. Secondary market prices for new and sealed sets typically fall between $40 and $50. Its post-retirement value lags behind similar retired sets, so the market for the set is easing.

Sea Serpent Value (New/Sealed)

This chart represents the current new/sealed value of the set Sea Serpent since July 2026. Medium accuracy
LEGO 40912-1 Sea Serpent is an Ideas Promotional set released in 2026, containing 241 pieces and 2 minifigures. The gift-with-purchase model is a modern remake of 6057 Sea Serpent from the 1992 Castle range and was based on the winning entry in the LEGO Ideas A Twist of Nostalgia challenge. It recreates a Black Knights ship with a black hull, blue railings, brown deck details, a front-mounted cannon, oars, shields, and an exclusive fabric sail printed with a red Sea Serpent emblem. The two Black Knights minifigures include helmets, weapons, updated shields, and torso designs reused from 21358 Minifigure Vending Machine.

A new and sealed Sea Serpent is currently valued at around $45. The average used price is $38 for those in good overall condition. New and sealed listings currently range from $40 to $50. Our forecast has the value rising about 8% over the coming year, to around $49.
Collector and Investor Standing
As a promotional item outside LEGO's regular store range, Sea Serpent gives Ideas collectors a fan designed take on a familiar ship. The fabric sail and moving rudders make the nostalgia tangible, while broad interest, frequent secondary market trading and the Ideas theme's steady history give investors plenty to like.
73/100
Collector
More sought after than most
Fan designed Ideas ship appeals to adults
75/100
Investor
A solid holding
Ideas history and frequent secondary trading
All regions

For Sale (New/Sealed)

 (CA) Ideas (CUUSOO) Sea Serpent 40912 $32.03
-29.6%
(US) Ideas 40912 Sea Serpent GWP New, Factory Sealed, Unopened
BrickEconomy Choice
$34.99
-23.1%
(US) Ideas Sea Serpent Set 40912 GWP SEALED $35.00
-23.0%
(US) 40912 Ideas Sea Serpent With Minifigures. 241 Pieces. $35.00
-23.0%
(US) IDEAS 40912 Sea Serpent Set Brand New GWP $35.00
-23.0%
(CA) Ideas - Sea Serpent - 40912 - Sealed - GWP Exclusive $35.78
-21.3%
(US) Ideas VIP GWP Sea Serpent - NISB - 40912 Limited Edition $35.99
-20.9%
(US) 40912 Sea Serpent - Ideas - Promotional GWP - New, Sealed, Retired $35.99
-20.9%
(US) #40912 Sea Serpent GWP: Brand New/Sealed $36.95
-18.8%
(US) New LEGO Ideas 40912 Sea Serpent Limited Edition $36.95
-18.8%
(US) Sea Serpent 40912 - NEW - SEALED - GWP - Castle $37.00
-18.6%
(US) Sea Serpent from BrickLink seller reskied $37.00
-18.6%
(US) IDEAS 40912 Sea Serpent New In Sealed Box 2026 $37.37
-17.8%
(US) Ideas Sea Serpent 40912 Limited Edition Set 241 pcs 18+ Box $37.50
-17.5%
(US) IDEAS Sea Serpent (40912) New in Sealed Box $37.75
-17.0%
(US) Sea Serpent from BrickLink seller septzoth $37.95
-16.6%
(US) Ideas #40912 Sea Serpent Limited GWP Ship Brand New Factory Sealed $37.99
-16.5%
(US) Sea Serpent from BrickLink seller bldgcelebration $37.99
-16.5%
(US) Ideas Sea Serpent 40912 Sealed $38.24
-15.9%
(CA) 40912 IDEAS Sea Serpent (BRAND NEW AND SEALED) $38.54
-15.3%
(CA) Ideas: Sea Serpent (40912) $38.54
-15.3%
Picked for your regionShow 41 more listings

Sales Distribution (Last 90 Days)

This chart shows the distribution of sales for the past three months of new/sealed 40912 Sea Serpent.

Market Momentum

Bearish
Listings for the 40912 Sea Serpent are fewer, but its value lags behind similar retired sets. Member interest is cooling as the retirement pop fades, leaving the market leaning down.
DemandLower half in Ideas
Very high demand but falling
12 months agoToday
SupplyMore than most in Ideas
Listings down 7% this month
12 months agoToday
Pop so far vs typical+6% typical
-22% value pop so far
Retired12 months
Outlook:53% bearish·40% neutral·7% bullish
Why it's moving, signals and outlook

Compared with other Promotional sets

Sea Serpent is well up among the Promotional sets for minifigures and draws fewer wanted lists per owner than most of the group's retired sets.

#5 of 14
By value, $45
$23$95
In the top half of the group.
$0.19 a piece
New and sealed value per piece
This set
$0.19
Typical
$0.18
Close to the group's typical value per piece.

Sets in Ideas / Promotional

40888 Godzilla Logo & Footprint

Theme / Subtheme Ideas / Promotional
Year 2026
Pieces 359
Availability Pending release
40888 LEGO Ideas Godzilla Logo & Footprint
Promotional
Not yet released
Available November 27

40487 Sailboat Adventure

Theme / Subtheme Ideas / Promotional
Year 2021
Pieces / Minifigs 330 / 2
Availability Retired
40487 LEGO Ideas Sailboat Adventure
promotional
Value $30.00
Annual growth 39.3%

40595 Tribute to Galileo Galilei

Theme / Subtheme Ideas / Promotional
Year 2023
Pieces / Minifigs 307 / 1
Availability Retired
40595 LEGO Ideas Tribute to Galileo Galilei
promotional
Value $45.00
Annual growth 5.5%

40698 Books Are My Passion

Theme / Subtheme Ideas / Promotional
Year 2024
Pieces 285
Availability Retired
40698 LEGO Ideas Books Are My Passion
promotional
Value $94.99
Annual growth 21.3%

40788 Friendly Snails

Theme / Subtheme Ideas / Promotional
Year 2025
Pieces 264
Availability Retired
40788 LEGO Ideas Friendly Snails
promotional
Value $47.63
Annual growth 4.3%

40566 Ray the Castaway

Theme / Subtheme Ideas / Promotional
Year 2022
Pieces / Minifigs 239 / 1
Availability Retired
40566 LEGO Ideas Ray the Castaway
promotional
Value $22.57
Annual growth 31.3%

40896 The X-Files Scully's Lab

Theme / Subtheme Ideas / Promotional
Year 2026
Pieces / Minifigs 221 / 1
Availability Retired
40896 LEGO Ideas The X-Files Scully's Lab
promotional
Value $89.99

40786 Micro Command Center

Theme / Subtheme Ideas / Promotional
Year 2025
Pieces / Minifigs 214 / 1
40786 LEGO Ideas Micro Command Center
promotional
Value $35.00

40789 Flying Moon Car

Theme / Subtheme Ideas / Promotional
Year 2025
Pieces / Minifigs 211 / 2
Availability Retired
40789 LEGO Ideas Flying Moon Car
promotional
Value $33.35
Annual growth 35.2%

40533 Cosmic Cardboard Adventures

Theme / Subtheme Ideas / Promotional
Year 2022
Pieces / Minifigs 203 / 1
Availability Retired
40533 LEGO Ideas Cosmic Cardboard Adventures
promotional
Value $24.99
Annual growth 5.1%

40448 Vintage Car

Theme / Subtheme Ideas / Promotional
Year 2021
Pieces / Minifigs 189 / 2
Availability Retired
40448 LEGO Ideas Vintage Car
promotional
Value $25.96
Annual growth 36.4%

40773 The Goonies The Walshes' Attic

Theme / Subtheme Ideas / Promotional
Year 2025
Pieces / Minifigs 179 / 2
Availability Retired
40773 LEGO Ideas The Goonies The Walshes' Attic
promotional
Value $84.97
Annual growth 17.2%

40889 Build, Paint and Play!

Theme / Subtheme Ideas / Promotional
Year 2026
Pieces / Minifigs 158 / 1
Availability Retired
40889 LEGO Ideas Build, Paint and Play!
promotional
Value $44.99

40335 Space Rocket Ride

Theme / Subtheme Ideas / Promotional
Year 2019
Pieces / Minifigs 154 / 1
Availability Retired
40335 LEGO Ideas Space Rocket Ride
Retail $12.99
Value $33.72
Growth  +159.6%
Annual growth 13.8%

Sea Serpent Questions

How much is LEGO 40912 Sea Serpent worth today?

Today's value for a new, sealed copy of Sea Serpent is $45. Sealed copies typically change hands for $40 to $50. Used copies are worth about $38.

Can you still buy LEGO 40912 Sea Serpent from LEGO?

No. LEGO retired Sea Serpent in July 2026. Collectors now buy it on the secondary market, from sellers on sites like eBay and BrickLink.

What will LEGO 40912 Sea Serpent be worth next year?

In twelve months, Sea Serpent could be worth around $49, about 8% more than today. That is the view for the year ahead. In the short term the market reads bearish. Demand, supply and price signals are leaning downward. Like any forecast, this is an estimate.

How big is LEGO 40912 Sea Serpent?

Sea Serpent has 241 pieces.

Top lists

My Collection

Sea Serpent Reviews

14 reviews
4.8
Collectors
Investors
Jays Brick Blog
“This model is a modern remake of 6057 Sea Serpent, which was released in 1992, and is likely a set that many of us have fond memories of playing. LEGO Ideas turned this concept into a model, as it was the winner of the A Twist of Nostalgia challenge, with HallowedBrick02’s... More Sea Serpent emerging triumphant amongst a field of retro-themed Ideas!”
Full review at jaysbrickblog.com
Brick Fanatics
“While 40912 Sea Serpent mirrors the overall shaping of the original submission pretty closely, there are still quite substantial changes to both the stern and bow when you look a little closer. Starting from the back of the ship, the squared-off modular stern now makes use... More of hinge plates to angle the side walls, which swing open to allow for internal access (rather than removing the roof).”
Full review at www.brickfanatics.com
Excerpts from third-party reviews

About Ideas Promotional

The LEGO Ideas theme, which started in 2008 as an offshoot of the Japanese website Cuusoo, then known as LEGO Cuusoo, is based around a website which allows users to submit ideas for LEGO products to be turned into potential sets available commercially. If fellow users in the LEGO Ideas community upvote the project to 10,000 then LEGO Group has a committee which votes on whether to build the set and release it.

Promotional was introduced in 2019 and currently consists of 15 sets. As of today, 40698 Books Are My Passion is the most valuable Promotional set with an estimated new/sealed value of $95.
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Ride a wave of nostalgia with the LEGO Ideas Sea Serpent (40912) building set for adults. Inspired by the Sea Serpent set first released in 1992, this reboot won the LEGO Ideas A Twist of Nostalgia design competition. Packed to the gunwales with details, this model ship kit includes a fabric sail, moving rudders and a cargo hold, plus 2 knight minifigures ready for high-seas adventure. Unlock a core memory for adult LEGO fans and collectors with this great gift idea. Set contains 241 pieces.

SHIP BUILDING SET Unwind with the LEGO Ideas Sea Serpent (40912) building kit for adults, a reboot of the 1992 Sea Serpent and the winner of the LEGO Ideas A Twist of Nostalgia competition

AWASH WITH DETAILS To capture the wind, and an authentic feel, this model ship includes a fabric sail, a modular stern, moving rudders, flags and a cargo hold

MEDIEVAL SWASHBUCKLERS Rekindle memories of endless play with 2 knight minifigures that bring the scene to life and spark nostalgic...
Description provided by LEGO©