Ages 6+

Kai's Dragon Mech Battle Pack (71851)

Name: Kai's Dragon Mech Battle Pack
Brand: LEGO
SKU: 71851
Rating: 4.8 (4 reviews)

Prices last checked: 1 May 2026 at 13:03

LEGO.com RRP:

£8.99

Best Price Found

€7.99(~£6.71) -£2.00 (22%)

View Deal →

Amazon FR// Last Checked: 1 May

LEGO.com

★4.8

(4 reviews)

★4.7

🧱 85 pieces - : £0.08

Available From

£6.99

£8.99

Free delivery

Save £2.00 (22% off)

Price checked: 1 May 2026

View Deal →

£7.99

£8.99

Save £1.00 (11% off)

Price checked: 1 May 2026

View Deal →

Best Deal

€7.99(~£6.71)

Price checked: 1 May 2026

View Deal →

£9.00

Price checked: 1 May 2026

View Deal →

LEGO.comOfficial

£8.99

Price updated: 1 May 2026

View on LEGO →

Building Instructions Brickset

Price Analysis

Lowest Price Ever

£6.71

at Amazon FR · Apr 2026

Average Price (12mo)

£8.61

Current vs Average

-7.2%

Below average

Price Trend

Falling

Last 30 days

Best Month to Buy

May

Value Score

10.0/10

Price-per-piece vs theme avg

The lowest price we've recorded for Kai's Dragon Mech Battle Pack is £6.71 at Amazon FR in April 2026. The current price is 7.2% below the 12-month average of £8.61. Prices have been trending downward recently — a good time to buy. Historically, May tends to offer the best prices for this set.

Price History & Buying Verdict

VerdictGood time to buy

•The current best price of £6.71 is within 5% of the all-time low we've recorded (£6.71 at Amazon FR, April 2026).
•Prices have trended downward over the last 30 days — there's a chance of a further dip.
•On price-per-piece, this is one of the better-value sets in the NINJAGO® range (value score 10.0/10 vs theme average).
•A recent price drop of about £3.28 was recorded in the last 30 days.

We've been tracking the price of LEGO NINJAGO® Kai's Dragon Mech Battle Pack (85 pieces) for 107 days, recording 24 data points across LEGO.com and major UK retailers. Over that period the price has dropped 5 times below previous levels, with the lowest price ever recorded being £6.71 at Amazon FR in April 2026.

The 12-month average sale price for set 71851 works out to £8.61 — that's 4.2% below the LEGO RRP of £8.99. The highest price we recorded across our tracked retailers was £9.99, giving a range of about £3.28 between the cheapest and most expensive observation.

Amazon UK has run the most price drops on this set in the period we've tracked, making it the retailer most worth watching for short-term deals. Historically, May has produced the lowest average prices for Kai's Dragon Mech Battle Pack, so if you're not in a hurry it's worth bookmarking the page closer to that window. Prices have been trending downward over the last 30 days.

Want to see how LEGO Kai's Dragon Mech Battle Pack (set 71851) compares against other sets? Browse the best-value LEGO sets or check the full price-history tracker.

Description

Kai's Dragon Mech Battle Pack (71851) is a LEGO NINJAGO® set with 85 pieces, with an RRP of £8.99. It's currently available from £6.71 at Amazon FR — 22% below the RRP, saving you £2.00. Prices have been falling over the last 30 days. With a value score of 10.0/10, this set offers excellent value compared to other NINJAGO® sets.

SpecificationsBoys, girls and fans of the NINJAGO® Dragons Rising TV show ages 6 and up can enjoy hours of imaginative play with the LEGO® NINJAGO Kai’s Dragon Mech Battle Pack (71851) building set. This playset features a dragon mech toy with posable legs, large wings, claw hands and an upper body that rotates 360 degrees, plus a cockpit to place a minifigure inside. This great value ninja toy also comes with 3 minifigures: Kai with 2 sword accessories, Sora with 2 swords and an Earth Monster toy with clawhands, letting kids enjoy hours of adventures as they act out scenes from season 4 of NINJAGO Dragons Rising. The LEGO NINJAGO range of building sets and adventure toys for kids includes detailed mechs, dragons and temples so fans can role-play awesome ninja action. Kids can build each playset with confidence using the LEGO Builder app – zoom, rotate in 3D and track progress with easy-to-follow digital instructions. Set contains 85 pieces.

Features

MECH TOY FOR KIDS – Kai’s Dragon Mech Battle Pack (71851) building toy lets boys and girls ages 6 and up role-play action from season 4 of the NINJAGO® Dragons Rising TV show
POSABLE DRAGON MECH – The dragon mech has posable legs, large wings, claw hands and an upper body that rotates 360 degrees, plus a cockpit to place a minifigure inside
3 NINJAGO® MINIFIGURES – This ninja toy comes with Kai, Sora and a villainous Earth Monster for fans to play out action-packed good vs. evil battles
ACCESSORIES – Each NINJAGO® character minifigure has at least 1 weapon accessory for enhanced play value: Kai has 2 swords, Sora has 2 swords and the Earth Monster has claw hands
SMALL GIFT FOR KIDS – This great value small LEGO® set provides a fun build-and-play experience and is a ninja gift idea for kids with a passion for fantasy and adventure toys
MORE NINJA ADVENTURES – Discover other LEGO® NINJAGO® toys (sets sold separately) featuring detailed mechs, dragons, temples and vehicles
A UNIVERSE OF LEGO® NINJAGO® SETS – This extensive collection of kids’ toys lets ninja fans and children escape into an immersive fantasy world for imaginative play with their ninja heroes
DIMENSIONS – This 85-piece ninja toy playset features a NINJAGO®dragon mech standing over 3.5 in. (9 cm) high

Frequently Asked Questions about Kai's Dragon Mech Battle Pack

What is the best price for LEGO Kai's Dragon Mech Battle Pack (Set 71851)?

The best current price for LEGO Kai's Dragon Mech Battle Pack (Set #71851) is £7.99 at Amazon FR. This is £2.00 cheaper than the official LEGO RRP of £8.99. Price last verified on 1 May 2026.

How much can I save on LEGO Kai's Dragon Mech Battle Pack?

You can save £2.00 (22% off) on LEGO Kai's Dragon Mech Battle Pack by buying from Amazon FR instead of LEGO.com. The official RRP is £8.99, but you can get it for just £7.99. Browse more top discounts.

How many pieces are in LEGO set 71851?

LEGO Kai's Dragon Mech Battle Pack (Set #71851) contains 85 pieces. At the best available price of £7.99, that works out to approximately 9.4p per piece.

What age is LEGO Kai's Dragon Mech Battle Pack suitable for?

LEGO Kai's Dragon Mech Battle Pack (Set #71851) is recommended for ages 6+. This set is part of the LEGO NINJAGO® theme. View all NINJAGO® sets and deals.

Where can I find the building instructions for LEGO Kai's Dragon Mech Battle Pack?

You can download the official building instructions for LEGO Kai's Dragon Mech Battle Pack (Set #71851) for free from LEGO.com. Download the building instructions here. The instructions are available as a PDF and can be viewed on any device.

Where can I buy LEGO Kai's Dragon Mech Battle Pack in the UK?

LEGO Kai's Dragon Mech Battle Pack (Set #71851) is available from 4 UK retailers including Amazon UK, Zavvi UK, Amazon FR and others. Prices range from £6.99 to £9.00. It's also available directly from LEGO.com at £8.99.

Is LEGO Kai's Dragon Mech Battle Pack on sale right now?

Yes! While not on sale at LEGO.com, you can get LEGO Kai's Dragon Mech Battle Pack for £7.99 at Amazon FR - that's 22% below the official RRP of £8.99. Browse more best offers.

What is the lowest price ever recorded for LEGO Kai's Dragon Mech Battle Pack?

The lowest price we've recorded for LEGO Kai's Dragon Mech Battle Pack (Set #71851) is £6.71 at Amazon FR in April 2026. That's 25% off the LEGO RRP of £8.99. Track the latest movements on our LEGO price history page.

Is LEGO Kai's Dragon Mech Battle Pack good value for money?

Comparing piece-count to price across the LEGO NINJAGO® theme, this set scores 10.0 / 10 for value. That works out to about 9.4p per piece. That puts Kai's Dragon Mech Battle Pack in the top tier of NINJAGO® sets for raw build value — you're paying noticeably less per brick than the theme average. Compare against other contenders on our best-value LEGO sets page.