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5521 – Back A

January 29, 2026January 31, 2026 Master Builder 3462 Views

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

Contributions

  1. Name, PDF and .io file submitted on January 29, 2026 by: livi
  • ← Space Skeletal Horse Concept

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About This Site

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

Useful Links

  • Submit Instructions!
  • New Instructions
  • New Official Sets
  • New Alternate Builds
  • Minifigs
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  • Medium Builds (<200 pcs)
  • Large Builds (<400 pcs)
  • Extra Large Builds (>400 pcs)
  • How BOTBB was Built

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The classic space set that never was.

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