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5521 – Back A

January 29, 2026March 4, 2026 Master Builder 4660 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
  • 5581 – Back A →

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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
  • BATMAN
  • Bionicle
  • Belville
  • Building Set with People
  • Castle
  • Duplo
  • Fabuland
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  • LEGOLAND
  • Model Team
  • Pirates
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  • Train
  • Town
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  • Western
  • More Sets
  • Misc

Useful Links

  • Submit Instructions!
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  • How BOTBB was Built

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The classic space set that never was.

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