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70437 LEGO Hidden Side Mystery Castle thumbnail image

70437 LEGO Hidden Side Mystery Castle
Images 6Description 
70437 LEGO Hidden Side Mystery Castle
  • Mystery Castle thumbnail
  • Mystery Castle thumbnail
  • Mystery Castle thumbnail
  • Mystery Castle thumbnail
  • Mystery Castle thumbnail
  • Mystery Castle thumbnail

LEGO 70437 Mystery Castle is a Hidden Side set valued at $222 for new and sealed sets, up 122% from an original retail price of $99.99. The set retired in August 2021 with annual appreciation averaging 7.65% since. On the used market, values range from $169 to $252 based on condition. Secondary market prices for new and sealed sets typically fall between $192 and $244. Market momentum for the set currently leans upward, with recent gains in value and thinning listings.

Mystery Castle Value (New/Sealed)

This chart represents the current new/sealed value of the set Mystery Castle since August 2021. Very high accuracy
LEGO 70437 Mystery Castle is a Hidden Side set released in 2020, containing 1,035 pieces and 6 minifigures. The build depicts a possessed castle with an observatory tower and a fold-out design for interior access. It integrates with the Hidden Side augmented reality app, enabling ghost-hunting and digital interactions when viewed through a smart device. The minifigures include Jack, Parker, Vaughn, Nehmaar Reem, and two Shadow-Walkers.

Mystery Castle has gained about 7.6% a year since it left store shelves, and a sealed copy now sits near $222. We forecast roughly 5% more over the next year. The average used price is $210 for those in good overall condition. New and sealed listings currently range from $235 to $265. The 6 included minifigs account for approximately 37% of the set's total value. The set was available for 14 months, from June 2020 to August 2021.
Collector and Investor Standing
Hidden Side collectors have good reason to notice this castle: its folding, possessed build works with the app, and Shadow-Walker and Nehmaar Reem appear nowhere else. Interest in it runs ahead of ownership.
63/100
Collector
A steady following
Shadow-Walker and Nehmaar Reem are exclusive
63/100
Investor
In the middle of the pack
Mystery Castle trades regularly on the secondary market
All regions

For Sale (New/Sealed)

 (KR) 70437 Hidden Side Mystery Castle 1035pcs (New, Unopened) $205.00
-7.7%
(AU) Hidden Side 70437 Mystery Castle (BNIB) $209.97
-5.4%
(CA) Hidden Side - 70437 - Mystery Castle $216.27
-2.6%
(CA) HIDDEN SIDE: Mystery Castle (70437) Set New Sealed Retired $228.78
+3.0%
(US) Mystery Castle from BrickLink seller greg_zielinski $229.00
+3.1%
(US) Hidden Side Mystery Castle 70437 - NEW Sealed - Halloween Haunted $235.00
+5.8%
(US) Mystery Castle from BrickLink seller seti587 $235.00
+5.8%
(US) Mystery Castle from BrickLink seller micbelt $240.00
+8.1%
(CA) HIDDEN SIDE 70437 MYSTERY CASTLE (2020) NEW SEALED VERY RARE $247.70
+11.6%
(US) Hidden Side Mystery Castle 70437 - NEW/SEALED/RETIRED/RARE- Halloween $249.00
+12.1%
(KR) 70437 Hidden Side Mystery Castle 1035pcs SEALED $249.04
+12.2%
(US) HIDDEN SIDE: Mystery Castle (70437) $249.50
+12.4%
(US) HIDDEN SIDE: MYSTERY CASTLE (70437) - SEALED - HALLOWEEN RARE $259.95
+17.1%
(US) Hidden Side Mystery Castle (70437) $265.00
+19.4%
Picked for your regionShow 4 more listings

Sales Distribution (Last 90 Days)

This chart shows the distribution of sales for the past three months of new/sealed 70437 Mystery Castle.

Sale Trends

This chart shows the sales trends of new/sealed 70437 Mystery Castle.

Market Momentum

Bullish
This set's value is climbing and listings are thinning out.
DemandLower half in Hidden Side
High demand
12 months agoToday
SupplyTypical for Hidden Side
Listings down 30% this month
12 months agoToday
Growth vs peers+5% typical for Hidden Side
+5% over the past year
12 months agoToday
Outlook:7% bearish·60% neutral·33% bullish
Why it's moving, signals and outlook

Sets in Hidden Side

70436 Phantom Fire Truck 3000

Theme Hidden Side
Year 2020
Pieces / Minifigs 760 / 5
Availability Retired
70436 LEGO Hidden Side Phantom Fire Truck 3000
Retail $59.99
Value $98.02
Growth  +63.4%
Annual growth 6.8%

70431 The Lighthouse of Darkness

Theme Hidden Side
Year 2020
Pieces / Minifigs 540 / 5
Availability Retired
70431 LEGO Hidden Side The Lighthouse of Darkness
Retail $49.99
Value $69.99
Growth  +40.0%
Annual growth 3.7%

70432 Haunted Fairground

Theme Hidden Side
Year 2020
Pieces / Minifigs 466 / 5
Availability Retired
70432 LEGO Hidden Side Haunted Fairground
Retail $49.99
Value $61.22
Growth  +22.5%
Annual growth 3.2%

70435 Newbury Abandoned Prison

Theme Hidden Side
Year 2020
Pieces / Minifigs 400 / 4
Availability Retired
70435 LEGO Hidden Side Newbury Abandoned Prison
Retail $39.99
Value $67.14
Growth  +67.9%
Annual growth 10.4%

70430 Newbury Subway

Theme Hidden Side
Year 2020
Pieces / Minifigs 348 / 3
Availability Retired
70430 LEGO Hidden Side Newbury Subway
Retail $29.99
Value $30.00
Growth  +0.0%

70429 El Fuego's Stunt Plane

Theme Hidden Side
Year 2020
Pieces / Minifigs 295 / 3
Availability Retired
70429 LEGO Hidden Side El Fuego's Stunt Plane
Retail $29.99
Value $39.98
Growth  +33.3%
Annual growth 4.8%

70434 Supernatural Race Car

Theme Hidden Side
Year 2020
Pieces / Minifigs 244 / 3
Availability Retired
70434 LEGO Hidden Side Supernatural Race Car
Retail $29.99
Value $39.99
Growth  +33.3%
Annual growth 4.1%

70433 J.B.'s Submarine

Theme Hidden Side
Year 2020
Pieces / Minifigs 224 / 3
Availability Retired
70433 LEGO Hidden Side J.B.'s Submarine
Retail $19.99
Value $37.58
Growth  +88.0%
Annual growth 6.5%

70427 Welcome to the Hidden Side

Theme Hidden Side
Year 2020
Pieces / Minifigs 189 / 4
Availability Retired
70427 LEGO Welcome to the Hidden Side
Retail $19.99
Value $37.23
Growth  +86.2%
Annual growth 9.6%

70428 Jack's Beach Buggy

Theme Hidden Side
Year 2020
Pieces / Minifigs 170 / 3
Availability Retired
70428 LEGO Hidden Side Jack's Beach Buggy
Retail $19.99
Value $21.81
Growth  +9.1%
Annual growth 1.9%

Mystery Castle Questions

How much is the Mystery Castle set worth?

Sealed in its box, Mystery Castle is valued at $222, with most sales landing between $192 and $244. That is up 6% on three months ago. A used copy in good condition goes for about $210.

Is LEGO 70437 Mystery Castle still available?

No. Mystery Castle left LEGO's shelves in August 2021 after a run of 14 months. Sealed copies are now found only on the secondary market, so the price follows what collectors will pay.

How has LEGO 70437 Mystery Castle performed since its release?

Mystery Castle has gained 122% on its original retail price of $99.99, or roughly 7.6% a year on average. That beats the Hidden Side average of 3.8% a year by a clear margin.

What is the one-year forecast for LEGO 70437 Mystery Castle?

In twelve months, Mystery Castle could be worth around $233, about 5% more than today. In the short term the market reads bullish too. Like any forecast, this is an estimate.

How many pieces and minifigures are in LEGO 70437 Mystery Castle?

The set contains 1,035 pieces, about $0.10 each at retail, with 6 minifigures: Jack Davids, Nehmaar Reem, Parker L. Jackson, Shadow-Walker (2) and Vaughn Geist. As a group the minifigures are valued at around $83, about 37% of the set's value, led by Nehmaar Reem at $37. Nehmaar Reem and Shadow-Walker are exclusive to this set.

Top lists

My Collection

Mystery Castle Reviews

29 reviews
4.9
Collectors
Investors
The Brothers Brick
“The Mystery Castle will be a nice addition for anyone looking to add a reasonably priced spooky castle to their collection. It doesn't have the color splash of the Scooby Doo Mystery Mansion, but the inclusion of lots of light blue colors in the transparent pieces and... More stickers keeps it from becoming boring. The astronomy tower in dark tan with its curved roof and large telescope makes for a nice accent to help this castle stand out from its predecessors.”
Full review at www.brothers-brick.com
New Elementary
“Overall I enjoyed the build experience, with a couple of minor exceptions where access was a bit limited. The finished model is quite substantial, and even without the accompanying app the Castle provides plenty of scope for ghost-hunting scenarios and play. It also offers... More potential for MOCing with interesting pieces if that is what attracts you to the set and its component parts.”
Full review at www.newelementary.com
Excerpts from third-party reviews

About Hidden Side

The LEGO Hidden Side theme was introduced in the summer of 2019 that was tech influenced and included a storyline and an app game (Apple App Store and Google Play). The theme is focused around the haunted town of Newbury and is designed with an augmented reality (AR) app, allowing users to capture ghosts while solving mysteries within the spooky town.
Summary
Hidden Side Mystery Castle set 70437 was released in June 2020, retailing for $100, but has since been retired. New, unopened Mystery Castle sets are valued at $222, while used sets can be found for $210.
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Fans of virtual reality and video games love the amazing LEGO® Hidden Side universe, where physical and digital worlds meet to provide an incredible, single or multiplayer augmented reality (AR) play experience. This LEGO Hidden Side Mystery Castle (70437) playset combines a buildable LEGO model with an app, so interaction with the model triggers events in a digital world.

The mystery castle springs to life when viewed through a smart device with the LEGO Hidden Side AR app. Children then get to explore, solve mysteries, hunt ghosts and battle boss ghost The Maw in an exciting digital world. The possessed castle model also folds out, setting the scene for action-packed role play with the Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures.
Description provided by LEGO©