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LEGO ETX Alien Mothership Assault

Set #7691 · 2007 · 434 pieces · Substantial build

LEGO ETX Alien Mothership Assault set 7691 instructions

Set Details

Set Number
7691
Name
ETX Alien Mothership Assault
Theme
Space
Year
2007
Pieces
434
Complexity
Substantial
Build Time
2-4 hours
Ages
10+
Type
Play-focused
LF
LegoFinder Editorial Team·Set data verified 2026·How we research sets

About LEGO ETX Alien Mothership Assault

LEGO ETX Alien Mothership Assault (set #7691) is a detailed build with 434 pieces from the Space theme, released in 2007. The Space line features spacecraft, moon bases, and interstellar exploration. This is a substantial-level build suitable for ages 10+, with an estimated build time of 2-4 hours.

Set Highlights

  • 434 pieces at substantial complexity — a 2-4 hours build.
  • Compatible with all standard LEGO sets — bricks extend naturally into other sets you own.
  • Play-focused build with interactive elements designed for 10+ builders.

Who Is This Set For?

Gift for Ages 10+

The substantial difficulty makes this accessible without being trivial — a well-matched gift for LEGO fans in the 10+ age range.

Weekend Build Project

434 pieces with an estimated 2-4 hours fits comfortably into a focused afternoon or weekend session.

Expanding a Space Collection

A solid addition for collectors building out their Space shelf. Introduces parts and builds that complement other sets from the same line.

Build Tips

1

A five-minute sort by color or piece type before starting saves time hunting for specific bricks mid-step.

2

Follow the numbered steps in sequence — structural elements early in the build support everything that comes after.

3

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 ETX Alien Mothership Assault (#7691) 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.

ETX Alien Mothership Assault FAQ

Related Reading

More Space Sets

See all Space →

Also Released in 2007

All 2007 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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