Set Details
- Set Number
- 75904
- Name
- Mystery Mansion
- Theme
- Scooby-Doo
- Year
- 2015
- Pieces
- 861
- Complexity
- Advanced
- Build Time
- 4-8 hours
- Ages
- 14+
- Type
- Both play and display
About LEGO Mystery Mansion
LEGO Mystery Mansion (set #75904) is a large, detailed build with 861 pieces from the Scooby-Doo theme, released in 2015. The Scooby-Doo line features mystery-solving adventure builds from Scooby-Doo. At 861 pieces, this is a advanced-level build with an estimated build time of 4-8 hours, suitable for ages 14+. As a licensed set, it recreates elements from the official Scooby-Doo property.
Set Highlights
- 861 pieces at advanced complexity — a 4-8 hours build.
- Compatible with all standard LEGO sets — bricks extend naturally into other sets you own.
- Versatile build — display-worthy when complete, durable enough for active play.
- Officially licensed Scooby-Doo set — faithful recreation of the source property.
Who Is This Set For?
Gift for Scooby-Doo Fans
The natural overlap between Scooby-Doo fans and LEGO fans makes this a go-to gift. The set brings recognizable characters and scenes into brick form.
Themed Play & Roleplay
Minifigures and themed accessories support imaginative play tied to the Scooby-Doo universe — the play experience extends well beyond the initial build.
Collector's Display Piece
Many fans build licensed sets and display them complete. Limited or retired licensed releases often gain value over time, making them popular with serious collectors.
Build Tips
A five-minute sort by color or piece type before starting saves time hunting for specific bricks mid-step.
Follow the numbered steps in sequence — structural elements early in the build support everything that comes after.
For active play sets, key connection points (hinges, turntables, clip joints) can loosen over time — a small dab of LEGO's own tube clutch lubricant on the stud resolves most looseness without damage.
Finding Instructions
Building instructions for LEGO Mystery Mansion (#75904) are available as a free PDF on LEGO.com. You can also upload a photo of this set to LegoFinder to identify it and access the instructions directly.
Mystery Mansion FAQ
Related Reading
More Scooby-Doo Sets
See all Scooby-Doo →
Also Released in 2015
All 2015 sets →Similar Build Difficulty
Sets at roughly the same piece count and complexity tier — different theme and year, but a similar build experience.
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