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Horus Heresy: Legion Leviathan Siege Dreadnought

Updated: Jan 16, 2023

Greetings one and all,

What has two legs, stands roughly 20ft tall and carries enough firepower to turn a battle? That’s right, it’s the subject of today's review: the Leviathan Siege Dreadnought. So, keep your heads down while we look up at this beast of a model.

For the few of your who are reading this asking what is a Leviathan Siege Dreadnought, the brief explanation is this; it is an armoured life support walker that houses the crippled body of a Space Marine, using some of the most advanced technological systems available at the time of the Great Crusade. This made it one of the most powerful Dreadnoughts the Space Marine Legions had access to, however, the use of such power required sacrifice. In the case of the Leviathan Siege Dreadnought, this was the mind of the Space Marine plotting it. A flame that burns twice as bright burns half and long.

Gamesworkshop recently (at least at the time of writing) released a fully plastic kit for this model, including a vast array of weapon options for both ranged and close combat. As well as this, they have continued their trend of releasing the Horus Heresy models at very reasonable prices. Beforehand, you would have had to get your Leviathan from Forgeworld at £58.50 for just the torso alone, and then a further £15.50 for each weapon which meant that a complete model would be £89.50, which is a lot. But now, you can pick up a Leviathan with all 6 ranged weapons for just £63.50 (and in case you were curious, this would have cost you £151.50 for the same loadout from Forgeworld). That is an insane saving. And it doesn't end there; you can pick up the weapons separately and there are the close combat weapons too, so overall, a really good kit.

But let's not get too far ahead of ourselves shall we? I’ve yet to tell you about the building process of the Leviathan Siege Dreadnought and I can tell you now, it is quite the process.

My first impressions, as someone who has built a number of the old Leviathans, gives me the ability to tell you straight away that this model is built completely differently from the old one. The box comes with 4 sprues; 3 are for the main body of the Leviathan itself, while the last one is for all of the weapons options. Looking at the instruction manual as well, it and the sprues are actually really good and very consistently numbered. Hell, even the angles of the pictures in the manual weren’t bad… Nice change.

Building the legs isn’t a challenging task. There are 2 possible poses though for you to choose from: the feet can either be glued flat, giving a stationary pose, or they can be positioned so that the Leviathan Dreadnought is stepping forward. The entire leg structure is made up of 9 pieces and I suggest dry fitting all of the parts first and then using slow setting super glue to get the pose you want, as it can be a little fiddly to manoeuvre the pieces into the right position and keep them there while the glue dries. For my model, I decided I wanted to make my Leviathan in its stepping forward pose, as I always found the weight of the old model restricted the level of motion, and now being plastic, it’s a lot lighter now giving it the ability to be able to handle its own weight.

So far so good, moving on to the body.

When it comes to the body I’m going to break it up into two parts: the abdomen and the torso.

The abdomen is fairly easy to build, but I did find some of the parts had a very tight fit. With parts numbered C57 and 4A in particular, I had to exert a good deal of force to get them to fit correctly. This might just be me, or my Leviathan, but I have found that the newer vehicle models do have very tight joints and fittings, and this isn’t only limited to the bipedal vehicles.

Other than that, the abdomen was fine. Which is to be expected, it's a 7-piece section after all.

Moving on to the torso, I found it a pleasure to build over the old Forgeworld resin model. When building this, I would recommend cutting out and cleaning all of the torso parts (making sure to lay them out in a clear way so you know which bit is which), then build the torso, rather than cutting it out and building as you go.

The main body and the sides were straightforward to build, but when putting on the armour plates, I would again suggest putting in the head and top plate first, then glueing what the build guide directs as parts 38 to 41 on. On the mention of those parts though; I found the joins between the parts numbered 38-39 and 40-41 didn’t fit together as well as I’d like, and I needed to apply a little more brute strength than originally anticipated when slotting them together after cleaning them up with a scalpel. But the finished result does look great.

Being a Dreadnought, weapons are going to be found everywhere on this thing and the torso, just like its original Forgeworld counterpart, can mount either two Heavy Flamers or a pair of twin-linked Volkite Calivers. What's better about this though, is that you don't have to decide which one you want and limit your loadout, because both the weapon types have 2 holes for 3mm magnets that line up exactly with a pair of holes in their slots on the torso (almost as though they were perfectly designed with magnetising in mind). I took advantage of this and decided to magnetise all the torso weapons, but if you do this bare in mind that the depths of the holes are different between the weapons and the torso. As a result of this, I used 3mm x 1mm magnets on the twin-linked Volkite Calivers and on the torso itself, and then used 3mm x 2mm for the Heavy Flamers because for some reason the holes on these weapons is slightly deeper, and I didn’t want to lose my magnets. It’s very easy to install magnets and having these holes readily in place to do this is a much-appreciated move by Gamesworkshop.

Moving on to the shoulders and arms. The whole section is made up of 8 separate parts, 3 for the shoulder and 5 for the arm and elbow joint itself; when Forgeworld made the Leviathan, the 3 parts making up the shoulder were all already constructed as a single piece, so having them now come separately now that they’re in plastic rather than resin was a small surprise, but honestly I prefer it this way as there is now more definition in the detailing of the armour plating and panels for the joint as a whole, which is nice. And when moving onto the arms, as with the torso and its mounted weapons there are more holes cut out to allow the installation of 6mm magnets. So it really seems that Gamesworkshop is listening to their fans and allowing us to get the most out of their models.

The weapons themselves are fairly intricate, especially the Grav-Flux Bombard. It’s a 15-piece weapon, which seems intimidating at first, but it goes together so easily it barely needs a guide. Each part goes where you think it does and it just fits very well. It also looks so cool, having so much detail and a nice amount of meatiness to it.

I’ve probably gone on enough about it by now, but each of these weapons comes with a 4mm hole in the elbow joint to enable magnetisation of these weapons, giving you the chance to swap out your loadout before each battle should you wish, which again, is such a great design decision from Gamesworkshop in my opinion because it makes the whole process so much easier and so much more accessible to people who may have less experience with this process and so might have found the idea a little intimidating.

With the arms and weapons now done, my Leviathan is complete.

Overall I found this to be a really fun and enjoyable build. I much prefer this new kit over the old resin one from Forgeworld; it is cheaper, there’s more availability of the weapons, and the fact it’s not made of resin held together with superglue means it’s lighter and easier to hold together under its own weight and should make it a lot less likely to break if it happens to get knocked off a table, which has happened to me many a time…

The Leviathan Dreadnought is very much well worth the money I think, and would make a great addition to any army.

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