More heavy armour for the Taghmata Omnissiah! Here’s the review for the Mechanicum Heavy Support Box, which contains three new kits: the mighty Thanatar Calix Siege-Automata, a heavily armed Karacnos Assault Tank, and the agile Krios Battle Tank. As always, there are high-resolution sprue images and all the build options.

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The Mechanicum Heavy Support box from Games Workshop's Horus Heresy game, on a white marble background, photographed for review purposes
This item was kindly provided by Games Workshop. Thoughts and opinions are our own.

The Mechanicum Heavy Support Box will be available for pre-order starting Saturday, 22 February 2025. The pre-order period lasts two weeks, with the official release date set for 8 March 2025. Please note that there will be only one production run, so the box is available only until stocks last.

Included in the box are:

  • a Thanatar Calix Siege-automata
  • a Krios Strike Tank (can also be built as a Krios Venator)
  • a Karacnos Assault Tank
  • 3 Mechanicum Macro Contructs transfer sheets and assembly guides
The contents of the Mechanicum Heavy Support box painted by the 'Eavy Metal team in a deep red, showing the Thanatar Calix, Krios tank, and Karacnos assault tank on a white background
© Copyright Games Workshop Limited, image used without permission

Mechanicum Heavy Support Force unboxing

The large-format box, made of sturdy, wrapped cardboard, is well-filled with a total of 11 large sprues. Let’s take a look at the three models included in detail.

Thanatar Calix Siege-Automata review

The Thanatar Calix Siege-Automata comprises one large and two medium-sized sprues, as well as a 120mm oval base, a black and white instruction booklet, and the Macro Construct transfer sheet. The transfer sheet offers a variety of symbols, but is only in black and white.

Mechanicum Macro Constructs transfer sheet on a white marble background
The Macro Construct transfer sheet, included once for every model in this box

The large and one of the medium-sized sprues are identical to the Thanatar Cavas kit; these build the automata’s torso. What’s new is the weapon sprue, which, unlike the Cavas, includes a sollex heavy-las for the shoulder and a graviton ram for the right arm. The kit allows you to choose between two leg poses, either with the right or left leg forward. The hip sits on a freely movable ball joint, and the shoulder joint of the right arm with the graviton ram is also a ball joint. For the left arm, as with the Cavas, you can choose between two poses for the twin-linked mauler bolt cannon; for this, ammunition belts in two different poses are included, which are connected to the ammunition feed on the back.

Sprue 1 of the Mechanicum Thanatar Calix Siege-automata kit, on a white background, photographed for a review of the Mechanicum Heavy Support Box
Sprues 2 and 3 of the Mechanicum Thanatar Calix Siege-automata kit, on a white background, photographed for a review of the Mechanicum Heavy Support Box

Patreon bonus content: Ultra high-res, uncompressed versions of these sprue images (and backsides of the sprues) can be downloaded here.

The Thanatar Calix, like its brother the Cavis, is a massive walker, similar in size to an Armiger Knight but with more width. The kit is challenging with many small parts and complex construction.

Karacnos Assault Tank

The Karacnos Assault Tank is based on the Triaros chassis, with whom it shares some of the kit’s total of 5 large sprues. Additionally, there’s an instruction booklet and a transfer sheet.

The identical sprue 1 and 2 of the Mechanicum Karacnos Assault Tank kit, on a white background, photographed for a review of the Mechanicum Heavy Support Box
Sprue 3 of the Mechanicum Karacnos Assault Tank kit, on a white background, photographed for a review of the Mechanicum Heavy Support Box
Sprue 4 of the Mechanicum Karacnos Assault Tank kit, on a white background, photographed for a review of the Mechanicum Heavy Support Box
Sprue 5 of the Mechanicum Karacnos Assault Tank kit, on a white background, photographed for a review of the Mechanicum Heavy Support Box

Patreon bonus content: Ultra high-res, uncompressed versions of these sprue images (and backsides of the sprues) can be downloaded here.

Two identical sprues build the track units on the sides, and two more sprues form the Karacnos’s hull. These sprues are identical to the Triaros. What’s new is the weapon sprue, which allows you to build the Karacnos mortar battery with either closed or open hatches. Also new is the upper armour, which is armed with flare shields and two lightning locks. Optional parts, like with the Triaros, include searchlights and hunter-killer missiles. The Karacnos weapon sprue also includes two optional antenna devices that you can place on the front of the hull.

Again, Games Workshop has succeeded in creating a faithful plastic reproduction of the resin kit. The fully detailed interior is also a nice touch. However, like the Triaros and the Thanatar Calix, the model is extremely complex to assemble, especially the lightning lock mounts, which consist of many small parts.

Krios Battle Tank

Last but not least is the Krios Battle Tank kit, also a plastic rendition of the previous resin version. This model comes on 3 brand new large sprues and can be built either as a Krios Battle Tank with a lightning cannon or irradiation blaster, or as a Krios Venator variant with a pulsar fusil. You also get an assembly guide and transfer sheet with this kit. All tanks feature optional volkite caliver sponsons as secondary armament.

Sprue 1 of the Mechanicum Krios tank, on a white background, photographed for a review of the Mechanicum Heavy Support Box
Sprue 2 of the Mechanicum Krios tank, on a white background, photographed for a review of the Mechanicum Heavy Support Box
Sprue 3 of the Mechanicum Krios tank, on a white background, photographed for a review of the Mechanicum Heavy Support Box

Patreon bonus content: Ultra high-res, uncompressed versions of these sprue images (and backsides of the sprues) can be downloaded here.

Aside from the choice of main weapon, there are no build options or optional cosmetic parts. Hunter-killer missiles or searchlights are missing. However, the main weapon can be tilted up and down, but you need to be careful not to glue the relevant sub-assemblies in place.

Value

The Mechanicum Heavy Support box is priced at £110 / 145 € / $185. The Karacnos is likely to cost £57 individually, like the Triaros. The Thanatar Calix, like the Cavis, should be £63.25, and I estimate the Krios to be around £42.50. This translates into a pretty nice saving of about 35 to 40% compared to buying them separately, and you can increase that saving by purchasing from our partners below.

(Pre)order the Mechanicum Heavy Support box

You can find the latest GW releases at our 🇬🇧/🇪🇺 partner stores Wayland Games, Element Games, and Firestorm Games, at 🇩🇪 Taschengelddieb and PK-Pro, and at 🇺🇸 Noble Knight Games with a welcome discount of up to 20% over RRP. Using our links helps to support Tale of Painters at no additional cost to you, so thank you very much for using them!

I hope you found this review helpful, feel free to leave a reaction or comment below, or post your questions here or discuss on our Discord channel.

9.0
Score

Pros

  • 3 all-new models
  • Faithful translations of their resin predecessors
  • Fairly high estimated discount

Cons

  • Highly complex models
  • Not that many cosmetic options
  • Transfer sheets are black/white only
Thanatar Calix
9
Karacnos Assault Tank
9
Krios Battle Tank
9

Final Verdict

A great box, filled with three brand new (but complex!) models for the Mechanicum. Thanks to the great savings, you won't get the included models cheaper than in this box. So, if you want some of it for your collection, you should grab it while the box is available.