LEGO® NINJAGO 71804 Arin's Battle Mech

The Lego set Arin's Battle Mech with the set number 71804 is part of the LEGO NINJAGO theme and is recommended for ages 4+. It was released in January 2024. It includes 4 minifigures. The model has 104 pieces, and we estimate it takes around < 1 hour to build. 37 Brickfact users have this set in their collection.
The set weighs about 0.231 kg. The box measures 20.5 x 19.1 x 4.6 cm. The recommended retail price is $15.99.
The Part-Out-Value (POV) is the sum of the average prices paid on bricklink.com for all parts of this set. It is about $16.69.

Lego 71804 product data

Set Information

Set ID
71804
Theme
Pieces
104
Building Time
< 1 hour
Age Range
4+

Availability

Release
01/2024
Retiring Status
Retired (12/2025)

Price Information

RRP
$15.99
Insiders Points (for purchase at Lego)
104
Part Out Value
$16.69

Packaging

Weight
0.231 kg
EAN (GTIN13)
5702017565545

Popularity with Brickfact users

users have this set
37

37 Brickfact users have Arin's Battle Mech in their collection.

Based on anonymized Brickfact user collections; shown only for sets with at least 10 users. As of November 1, 2026.

LEGO 71804 price trend

Average sale price on secondary marketplaces – not the new price at retailers.

Current market value
$12.66
Growth vs. RRP
−20.9 % $15.99
Range
$10.77 – $12.81
Average
$11.66

Loading price history…

LEGO 71804 price history: how has the price changed?

Brickfact has been recording retailer prices since 10/12/2026. Best price so far: $35.48 (21 days ago).

Best price since 10/12/2026
$35.48 +122% vs. RRP · 21 days ago

Daily lowest prices at the tracked shops, including shipping. Gaps indicate days with no recorded price. The table lists each shop’s lowest price.

Lowest price per retailer (since 10/12/2026)

RetailerCurrentLowest priceDate
Bestbuy.com–$35.4810/22/26

Lowest price per day that Brickfact recorded at the retailers in the price comparison, including shipping where known – as in the comparison above. Amazon offers are not included in the price history.

Minifigures from 71804 Arin's Battle Mech

The Arin's Battle Mech set includes 4 different minifigures, 2 of which are unique to this set. The combined value of the minifigures is $8.43, which is ~53% of the RRP of this set.
x1
Thumbnail of minifigure njo0850
Arin - Shirt with Orange Dragon, Head Wrap
NINJAGO
time-logo
2024
#njo0850
$2.40
i
Unique
x1
Thumbnail of minifigure njo0851
Wolf Mask Warrior / Wolf Mask Claw Warrior - Dark Blue and Dark Azure Mask, Shoulder Armor
NINJAGO
time-logo
2024
#njo0851
$1.87
8 sets
x1
Thumbnail of minifigure njo850
Arin - Head Wrap
NINJAGO
time-logo
2024
#njo850
$2.33
Unique
x1
Thumbnail of minifigure njo851
Wolf Mask Warrior / Wolf Mask Claw Warrior - Shoulder Armor (71802, 71803, 71804, 71805, 71806)
NINJAGO
time-logo
2024
#njo851
$1.83
8 sets

Official Set Description for LEGO 71804 Arin's Battle Mech

Arin’s Battle Mech (71804) ninja toy lets kids aged 4+ learn to build as they join in with their ninja heroes’ attempt to save their dragon friends. This role-play action toy includes an impressive mech figure to inspire kids to recreate exciting adventures from season 2 of the NINJAGO® Dragons Rising TV show.

This LEGO® set comes with 2 minifigures: Arin with a katana accessory and a Wolf Mask Warrior with a sword accessory. Arin fits in the posable mech figure, which wields a large sword androtating blade, while the Wolf Mask Warrior can fly in a glider that has posable wings, a disc shooter and 2 spears. There’s also a brick-built crystal cave with a magic mallet inside and a weapons rack with 2 golden katana sword accessories.

This ninja toy has been designed to provide a fun experience for children aged 4+ who are discovering the joy of building with LEGO bricks. The set comes with a Starter Brick: a partly constructed base that gets kids building quickly and with confidence.

  • Learn-to-build ninja toy for kids – Boys and girls aged 4 years old and up can discover the joy of building and play out ninja stories with the all-action Arin’s Battle Mech playset
  • Posable mech toy – Kids can recreate battles from season 2 of the NINJAGO® Dragons Rising TV show with this mech figure featuring a cockpit, posable limbs, rotating blade and large sword accessory
  • 2 LEGO® NINJAGO® minifigures – Ninja playset includes an Arin minifigure armed with a katana accessory so kids can role-play action against the Wolf Mask Warrior with his sword
  • Flyer and crystal cave – Role-play toy set includes a flyer with posable wings, a disc shooter and 2 spear elements, a crystal cave with a magic mallet, and a weapons rack with 2 katana sword elements
  • Ninja gift – LEGO® set provides a fun build-and-play experience and is a gift idea for kids aged 4 and up to fuel their imaginations and develop their storytelling skills
  • Discover more ninja toys for kids – Look out for other NINJAGO® playsets (sold separately) featuring dragons, mechs and ninja legends
  • Introduction to building with LEGO® bricks – 4+ LEGO playsets help youngsters learn how to build, while allowing the rest of the family to share in the fun
  • Measurements – 104-piece LEGO® set with a mech toy standing over 4 in. (10 cm) tall

Building Instruction for LEGO 71804 Arin's Battle Mech

LEGO 71804 Frequently Asked Questions

Is LEGO 71804 still available?
LEGO has retired 71804 Arin's Battle Mech, and no retailer in our price comparison currently sells it new. Its market value on secondary marketplaces is $12.66.
When was LEGO 71804 cheapest?
Since tracking began on 10/12/2026, the lowest shop price recorded by Brickfact for LEGO 71804 was $35.48 on 10/12/2026 at Bestbuy.com, including shipping. Amazon prices are not included.

All LEGO NINJAGO sets from 2024

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