Adeptus Mechanicus Eradication Cohort, how to cast gun and win

Games Workshop has given Adeptus Mechanicus a much nastier lane to play, and the Eradication Cohort is the detachment that makes the point loud and clear: this is about real damage, real pressure, and real wins, not just standing in the back and looking efficient. Floof’s deep-dive for Goonhammer lands on the exact question AdMech players keep asking whenever a new package drops: how do you turn the faction’s machine discipline into a game plan that actually breaks the opponent?

What Eradication Cohort is really asking you to do

The faction pack frames Eradication Cohort as a force that “focus[es] on purely offensive strategies,” and that is the cleanest way to understand it. The style is not a static gunline that hopes to survive long enough to score later; it is built around “blistering close-ranged firefights” followed by fanatical charges, which means you need to think in terms of tempo, angles, and repeated pressure. If you are treating the detachment like a cautious castle, you are missing the point before the first dice are rolled.

That matters because AdMech has long been the army people buy when they want a rules puzzle. The Eradication Cohort gives that puzzle a very specific answer: get close, hit hard, and keep the opponent under stress so they cannot reset the board. The new toys are not there to make your units prettier on paper, they are there to make your turns more violent and more connected.

The core game plan: pressure, then pressure again

The winning rhythm here is simple, even if piloting it well is not. Push pieces into range where they can force immediate decisions, use ranged damage to crack open the target, and then keep the opponent from breathing by following with charges and movement tricks. The faction pack’s own wording makes the sequencing obvious: the cohort wants shooting to set up the melee, not shooting as an end in itself.

That is why Unrelenting Aggression matters so much. The stratagem lets an Adeptus Mechanicus unit act after Falling Back in the Movement phase, which is exactly the kind of rule that keeps an aggressive army from getting pinned down by a single bad touch. In practice, it means your pressure pieces can get trapped, leave combat, and still function, instead of wasting a whole turn because the opponent managed to tag the wrong unit.

That one rule changes how you think about board state. A lot of older AdMech builds were about preserving assets and minimizing exposure, which is sensible until you realize the opponent is happy to use that caution against you. Eradication Cohort wants you to trade a little safety for a lot of initiative, then use mobility and fallback play to keep the momentum alive.

Which units and roles matter most

The guide Floof is writing toward, and the detachment design itself, both point to the same thing: the army works when its parts are doing different jobs at once. Your shooting engine needs pieces that can actually reach the fight, your pressure pieces need to threaten the mid-board, and your support elements need to keep the whole machine from stalling. The detachment is not asking for a single death star, it is asking for a chain of threats.

That is why target priority becomes so important. You do not waste your best output into something the cohort cannot finish, and you do not let a fast enemy piece live long enough to break your formation. The best turns are the ones where your guns open the lane, your follow-up threatens the objective, and your opponent is forced to choose between losing units or losing position.

If you want a practical rule of thumb, it is this:

• Shoot the piece that blocks your next move, not just the biggest visible target.
• Use charges to trap the enemy after the shooting sequence, not as a panic button.
• Keep one eye on what happens after a unit Falls Back, because Unrelenting Aggression can turn a dead turn into a live one.

That is the difference between a detachment that looks lethal and a detachment that actually wins games. You are not just collecting damage numbers, you are engineering a turn cycle the other player cannot comfortably answer.

The mistake most AdMech players will make

The biggest trap is trying to pilot Eradication Cohort like older Adeptus Mechanicus builds. That old habit says, “protect the fragile guns, establish a neat firing lane, and hope the opponent comes into you.” Eradication Cohort is much less polite than that, and if you keep waiting for the perfect castle, you will hand the mid-board to faster armies and let your offensive tools rot on the edge of the table.

This is especially dangerous because AdMech still has the same identity problems that made earlier builds feel punishing. The army can be fragile, the rules overhead can be demanding, and the margin for sloppy movement is tiny. Eradication Cohort does not remove that burden; it rewards you for solving it aggressively instead of defensively. You have to commit with purpose, not drift forward and hope the detachment does the rest.

Why this matters inside the wider AdMech toolbox

Eradication Cohort is not the only way to build Adeptus Mechanicus, and that is part of the appeal. The 10th edition codex gives the faction five themed detachments and, by the codex’s contents, 30 datasheets, so this is one lane in a broader toolbox rather than the only legal answer. That breadth is exactly why the cohort stands out: it gives AdMech a clearly aggressive identity inside a faction that still offers other build paths.

It also arrives as part of the Eye of Terror rules wave, which ties the detachment to a broader campaign package rather than a standalone tweak. Warhammer Community’s Eye of Terror coverage puts Adeptus Mechanicus in the same release conversation as Imperial Knights, and that wider context matters because it shows Games Workshop is reshaping faction roles through campaign-era rules, not just through full codex drops. The old Eye of Terror, with the Cadian Gate at its center, is back in the rules spotlight, and AdMech is being pushed into a more ruthless posture inside that setting.

That is what makes the Eradication Cohort worth learning properly. It is not a gentle upgrade to an old list style, it is a push toward a sharper, more aggressive AdMech that rewards sequencing, target priority, and the nerve to keep moving after the first engagement. If you cast the guns right, the cohort does not just shoot well, it keeps the whole table on the back foot until the game breaks open.