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LEGO Alternate Builds!

SETS
- Adventurers
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- BIONICLE
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Alternate Builds Instructions Added Large Alt Build Large Builds Model Team Model Team Alternate Builds

5521 – Back A

January 29, 2026March 4, 2026 Master Builder 4513 Views

From: 5521: Sea Jet
Name: TBD ¹
Instructions: View PDF | Download .io File

Contributions

Name, PDF and .io file submitted on January 29, 2026 by: livi

← Space Skeletal Horse Concept
5581 – Back A →

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About This Site

There were once pictures of additional LEGO® builds on the back of set boxes. Written on the boxes was typically something about the endless building possibilities, "Build any of these exciting models with this set!" There were no instructions for these alternate builds, until now.

Sets

Adventurers
Aquazone
BATMAN
Bionicle
Belville
Building Set with People
Castle
Duplo
Fabuland
Harry Potter
Holiday and Event
LEGOLAND
Model Team
Pirates
Space
Star Wars
Technic
Train
Town
Universal Building Set
Western
More Sets
Misc

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New Alternate Builds
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Small Builds (<100 pcs)
Medium Builds (<200 pcs)
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How BOTBB was Built

In Honor of 1526

The classic space set that never was.

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