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Reznor Knockdown Expansion Set — LEGO set 71390

Official LEGO® image · © LEGO Group and/or the respective rights holders. Source: LEGO Italy ↗

Super Mario · SET 71390

Reznor Knockdown Expansion Set

A large challenge with Reznor and walkways.

Pieces
862
Release year
2021
Theme
Super Mario
Set number
71390
LEGO recommended age
8+
Historical price in EUR
Not verified
Official LEGO archive Official building instructions

The historical euro price has not been verified. No current offer or conversion from another market is shown.

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Official English name verified at: LEGO English archive ↗ · Checked on 26 October 2026.

TIME TO BUILD

How long does it take to build Reznor Knockdown Expansion Set?

First build · with help if needed

For younger children, we estimate the first illustrated setup, with adult guidance when needed. Ranges reflect building familiarity, not a child’s age or ability. Free play and learning have no completion time.

Editorial estimate · first setup

Beginner

≈ 6 h 15 minSuggested range3 h 45 min – 10 h

Intermediate

≈ 4 h 15 minSuggested range2 h 30 min – 6 h 45 min

Experienced

≈ 3 hSuggested range1 h 45 min – 4 h 45 min

First guided arrangement: one model for 3 in 1 sets, a small composition for creative boxes, and setup alone for expansions. Excludes play, breaks and electronic configuration. These are broad editorial estimates, not measured times or targets to meet.

How we estimate times · sources and method

Editorial assessment: A large challenge with Reznor and walkways. Several brown and grey platforms form the course. Creative boxes and modular decorations refer to one first illustrated arrangement; 3 in 1 sets to the main model only, and expansions to their first setup. An adult may guide the child. Ranges reflect building familiarity, not age or development; they do not measure play, learning or a speed contest. For older sets, unnumbered bags or previously mixed pieces may prolong sorting. No verified timed build: indicative values with substantial variation.

Sources do not always specify the builder’s experience. The three experience bands are our editorial assessment, based on the complexity of the set and individual accounts where available.

Checked: 26 October 2026 · Method v1.0 · Limited reports; not a statistical average.

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BEYOND THE BRICKS

Did you know?

The model, the history, the ideas

Inside the set

01

A closer look

Characters are arranged along a tall structure.

LEGO source
02

Another detail

Several brown and grey platforms form the course.

LEGO source

Beyond the set

The stories, places and inventions behind your build.

03

Yoshi arrives on Super Famicom

Super Mario World launched in Japan on 21 November 1990, introducing Yoshi as a later star in his own right.

Nintendo
04

Dinosaur Land adventure

Mario and Luigi rescue Peach with actions including cape flight and Yoshi riding.

Nintendo

Written by HowLongToBuild · Sources are linked with each story · Checked on 26 October 2026. Historical facts and story details refer to the context described.

THE COMMUNITY’S EXPERIENCE

What was it like to build?

Three separate scores from 1 to 10. For difficulty, 1 means very easy and 10 means very difficult.

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Building tips from the community

Specific steps, useful checks and sticking points. Contributions appear after moderation, in their original language. Do not upload instruction pages or personal contact details.

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SET THE MOOD

A soundtrack for your build

Reznor Knockdown Expansion Set · Selected for the subject and atmosphere

Electronic pulses and alternating motifs suit modular shapes and digital worlds. This is not the game’s official music: we choose the musical language for the act of building.

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Editorial suggestions, not official soundtracks for the set. External services may require an account or subscription; editions and availability can vary by country. Suggest another soundtrack →

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YOUR NEXT BUILD

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