The Horus Heresy: the Siege of Hydra Cordatus and Iron Warriors Dominator Cohort

Three new units and accompanying mini campaigns in as many months? The Warmaster is truly smiling on us! It looks like we’ll be getting one of these on the first Monday of every month, so let’s dive in and see how the Iron Warriors fare in the Siege of Hydra Cordatus!

Credit: Robert “TheChirurgeon” Jones

The Siege of Hydra Cordatus: the Sundering of the Cadmean Citadel

What’s neat about this month’s exemplary battle is we get a bit of a prequel to the Graham McNeill book Storm of Iron, which details the second Siege of Hydra Cordatus in moderately horrifying detail. This campaign details a bit of a Perturabo temper tantrum, where to prove he’s not a terrible Primarch who almost got killed by an Imperial Fist who wasn’t even supposed to be in charge he decides to assault the world with Hydra Cordatus on the ground, rather than raising it from space. We’re treated here to an interesting story of how Perturabo’s stability starts to slide almost as fast as Curze, but in a different direction; the mere presence of an Imperial Fists garrison force (which they left everywhere they could, pretty much) draws Perturabo’s personal attention.

I was expecting a fairly bland story, to be honest, with another set piece battle between Imperial Fists defending a fortress and Iron Warriors attacking, but when you see phrases like “it seemed as if the citadel itself came to life… cavernous maws opened in the ground to swallow entire squads of Legionaries… impaled upon stony protrusions that erupted from the ground driven by the will of the fortress… semi-sentient fortress”, you’ve got me hooked. Honestly, the way this story is told it almost seems like it should be the other way around, a sinister fortress powered by the cruel intellect of the Dark Mechanicum. Once more we see a traitor captain rising about his station only to be brought low by those he called allies, but overall this is the most enjoyable of the three exemplary battles to read so far. The story doesn’t show an end, but with the Hammer of Olympia landing it seems only a short while before the bold boys in yellow meet their doom.

The campaign itself is interesting, with the first scenario, the Iron Tide, being played up to three times on three different maps before moving on, representing the different fields of battle where the Iron Warriors threw waves of their own soldiers at the defenders for little gain. While hypothetically these missions use variable game length, the fact that both Legions here have a special rule allowing their opponent to ignore variable game length means you’re going to have a full six turn slog fest almost every time. The defender here scores 1VP per objective held (D3+3 placed across the board) , while the attacker scores between zero and two depending on a D6 roll. Secondary objectives are fantastic here; the Iron Warriors score bonus victory points for slaying the enemy warlord and getting right up close to the defender’s table edge, while the Imperial Fists score for having more units left alive. 

The second mission, Vengeful Strike, is a Zone Mortalis “kill them all” type mission where the First Line (defenders units deploying not as reserves) are stubborn against the whole weight of the attacking army, but, more importantly, the fortress eats people. Those D3+3 objective markers you used in the last scenario? Now you can use them as markers for where, if an attacking unit ends its turn within 2”, they can varyingly be subject to Crushing Mass as the walls come alive, Graviton pits punishing the weak, and Bio-absorbers where the fortress, quote, “voraciously swallowing and digesting their matter even as they struggle to break free”. Hell. Yeah.

Credit: Robert “TheChirurgeon” Jones

Iron Warriors Dominator Cohort

The Tyranthikos, or Dominators,  were Perturabo’s first bodyguard, guarding the paranoid primarch until their failure at the Battle of Phall nearly led to his death at the hands of Alexis Polux, the Crimson Fist. Replaced by Iron Circle Domitar-Ferrum class Battle-Automata of the Lord of Iron’s own design, the Dominators became increasingly resentful of their Legion command and the robots that had replaced them. 

Bottom line up front, this is a unit of 5-10 Cataphractii terminators all armed with combi-bolters and thunder hammers, which is pretty neat, WS5, Stubbornness and a Hatred for models with the Cybernetica Cortex special rule. This is a unit that fits the Iron Warriors to a T, because they’re… well, very angry, not great, and liable to make IV Legion players a tad bitter. For 100 points more than a basic terminator squad, you’re getting WS5, Stubborn, Hatred (Cybernetica Cortex), and 50 points worth of mandatory thunder hammers. Is 100 points worth all that? Maybe, and the discount does get better at max squad size, but what purpose do they have in your army that you aren’t already filling with Iron Circle (better at smashing) or Siege Tyrant terminators (better at dakka and better at being terminators)? Hell, even basic Legion terminators can do the whole ‘not dying’ thing pretty well, and for a lot cheaper points cost.

It’s unlikely to be anti-robot duty, because On the other hand, if you’re throwing these against Automata their special rule is unlikely to come into play, because they’re striking last with their thunder hammers against higher initiative robots with AP2. Sure, you still have a 4+ invulnerable save to protect you, but a similarly priced unit of Vorax or even Castellax is going to wipe out half your expensive terminator unit before you do, uh, a single wound back per swing of a thunder hammer. Yay? In all honesty, my view on this may be slightly tainted by the fact that I am a Mechanicum player at heart, and while the lore and rules of this unit push them towards anti-automata action, I’m just really not that worried or impressed by them. Yes, they can re-roll misses in the first round of combat, but Preferred Enemy grants them re-rolls of 1 to hit and wound all the time. Part of the issue here is the plethora of rules that do very similar things; hopefully kindred rules like Hatred, Preferred Enemy and Zealot can be cleaned up a little going forward.

Just like the Atramentar and Huscarls the Dominators get a unique bodyguard special rule. You can take a Dominator Cohort as a bodyguard for Perturabo, where they lose their bitterness against automata and gain Feel No Pain 6+, but your army can’t take Iron Circle (because if Perty is with these guys, Phall hasn’t happened yet).

It’s important to note that Thousand Sons Castellax-Achea battle-automata do not have the Cybernetica Cortex special rule, because they are wizard robots, which is rad as hell, but I think we can all agree that Dominators should benefit from Hatred against these robots as well.

The lore here is pretty wicked, and it’s great to see a super tight lore:rules interaction, but you’re not going to see these outside of the fluffiest of IV Legion armies. Of the three Legion unique terminator squads we’ve seen so far from these Exemplary battle drops, the Atramentar are the clear and terrifying winners, the Huscarls do pretty decent work, and the Dominators should’ve been left back on Olympia.

Iron Within, Iron Without!

Three exemplary battles down, and who knows how many to go? This is the most interesting battle yet, even if the accompanying unit is a bit naff. No one is going to accuse you of powergaming if you bring a unit of Dominators, but it’s always a bit disappointing when your shiny new Cohort ends up being almostvas much of a disappointment on the table as they are to their Primogenitor. They’re not the worst unit we’ve seen in the Heresy to date by a long shot, and I’m really looking forward to seeing what Iron Warriors fans can do for conversions. It’s just… Perturabo has had a real tough time of it lately, and it would be nice for him to have something nice happen to him for once, y’know? 

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