Editing Warhammer 40,000/9th Edition Tactics/Adeptus Mechanicus (section)

=== Army Composition and tactics ===
There are some starter list archetypes as an example. Open the fourth one if you dare.
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<tab name = "The Navy">
Take a bunch of D-Day landers (transports), fill them with infantry, storm the beaches, rush to the objectives and hold them. Often a custom FW. This is our mechanised option and the TAC variant and is often supported by some backfield artillery fire in a second Stygies detachment. (Cawl isn't worth it if you can't feed him enough units to buff so the survival option is generally better.) A nice all-round option, but the more specialist options may outperform it if played correctly. This style also has the advantage of letting you lean more into infantry or vehicles, giving you more flexibility in how you want to grow your list. Unlike with the Skitarii horde, if the lascannons are hitting your boats they're not hitting your artillery. Its downsides are that it is not as killy as the crusher and not as great at the mission as the horde but neither does it have their weaknesses.
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<tab name = "The Infantry">
Take 6 large units of Vanguard, 3 max units of Raiders, 3 units of 10 Hoplites and some Corpuscarii reserves, and we have the core of a Skitarii horde. Take in Ryza or an expansionist Forgeworld and swarm the objectives - this is the board control list. You're gonna be a lot less shooty than the others, but you're not limited by the need to play within buff range. While our infantry is pretty solid for its points meaning they can hold the board and objectives. This is a build designed to play the mission, not kill your opponent. The other problem with the horde is that if you try and add one or two vehicles to it, all your opponents' lascannons or equivalent will target them and they will evaporate, whereas if you have no vehicles, the lascannon are wasted on a Vanguard. In practice this means ignoring our vehicle options.
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<tab name = "The Ranger Firing Squad">
Something to note before even considering attempting this is that this setup is not meant to be the entire list, but a nice backbone for any firing line you may set up. It does require aura/placement synergy between four (optionally five) units to turn a standard block of 20 Rangers into a downright disgustingly lethal shooting unit that can absolutely blend MEQs and butcher anything short of a Knight statline.

This setup requires the following:
*To start, a block of 20 Skitarii Rangers to form the 'Ranger Firing Squad' part of the setup. Everything else is only there to buff these guys, so paying some extra points for wargear isn't a terrible idea. +10 points for the Omnispex to ensure that what you're shooting at will get hit and another 10 for the Enhanced Data-Tether will help with morale, in the unfortunate event that whatever you send your withering hail of firepower at has enough working limbs left during their turn to shoot back.
*A Tech-Priest Manipulus' Galvanic Boost ability will substantially buff their guns, making them go from 30" AP-1 to 36" AP-2. The extra range will help with shooting without needing to worry about taking shots back, and the extra AP point will go a long way to ensuring that whatever you hit will die. In addition, you should give this unit either the Magi or the Artisans Holy Order. Magi will give your Rangers an extra hit on unmodified 6's, which is great. Artisans will bump up the Rangers' rifles to Strength 5, which means you'll be wounding MEQs on 3+. 
*A Skitarii Marshal given the Exemplar's Eternity Relic will give your Rangers the ability to reroll hit rolls and wound rolls of 1, which is obviously useful.
*A Tech-Priest Enginseer will be a carrier for whatever Holy Order you didn't give the Manipulus, meaning that both of them combined will buff the guns to an insane degree. It is a lot of points, though, so it may be a good idea to make him pull doubletime on an Onager or something, which is why I prefer to use an Enginseer for this over a Technoarchaeologist.

This is already very good, but can be made even better. The Galvanic Volley Fire Stratagem increases your output of fire by 50%, leading to 60 shots from a full unit, while the Protector Doctrina will let your Rangers hit on 2+. Finally, taking another Enginseer (or Technoarchaeologist) and giving him the Logi Holy Order will let your Rangers shrug off AP-1 and AP-2, which has the potential to completely kneecap your opponent's shooting. Keep in mind that doing that last bit will add another 95 points to this setup, so it's your choice as it isn't strictly needed.

*Finally, the Forge World buffs. Most of these are pretty nice, but you can choose whichever. Agripinaa will improve your guns' AP by -1 when firing at a target within half range, which may bump up your guns to AP-3. Lucius will give your guns an extra 3" of range and a free +1 to the Armor Save when shot at with a Damage 1 gun when out in the open, which is handy. Mars will let you reroll a hit and wound roll (the damage roll reroll is useless here), which is nice, but the real benefit is getting access to Canticles and the Wrath of Mars Stratagem. Metalica will let you move and shoot without penalty. Stygies VIII gives you the benefits of Dense Cover if being shot at from over 12" away. Ryza is useless.
*Custom Forge Worlds are also pretty good here. The Rad-Saturated Forge World debuffs ranged attacks that hit your guys with -1 Strength. The main buff from the Expansionist Forge World isn't great, but the Acquisitive Reach secondary trait gives your Rangers' rifles an extra 6" of range. Finally, the Reignited Forge World is essentially just a worse Agripinaa, but take it for the secondaries if you like.

In the end, we have turned a group of 20 infantry firing 40 shots at BS3+ 30" S4 AP-1 D1 into 20 infantry (potentially ignoring AP-1 and AP-2) firing 60 shots at BS2+ 36" (or 39" or even 42") S5 AP-2 (or AP-3, depending on the Forge World) D1, with rerolls of 1 to hit and wound with exploding hits on 6s, which statistically gets you 70 hits from 60 shots, all for the low price of 435 points (not including wargear). If you really wanted to be That Guy, leaving out the Logi carrier and putting the first Enginseer into Brotherhood of the Cog means that this setup is technically legal for a 500 point Patrol Detachment.
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<tab name = "The Skittle Rad-Horde">
This setup requires the following:

* Rad-Saturated Forge World with Scarifying Weaponry: SW is pretty much the only useful dogma for the RSFW, and the sheer number of Vanguard in this list make heavy use of its +1 to Strength and AP.
*Four bricks of 20-model Skitarii Vanguard, with two plasma calivers on two of the bricks, two arc rifles for each squad, and an omnispex on all of them. These guys are the backbone of your gunline; the arc weapons and plasma calivers will tear chunks out of vehicles and do some manage to TEQs, while the carbines can be combined with Enriched Rounds once per shooting phase to near-delete a MEQ unit.
* Three Skitarii Marshals: one with Exemplar's Eternity and Firepoint Telemetry Cache, one with Programmed Retreat and The Cage of Varadimas, and one with Multitasking Cortex.
** The Marshal with Exemplar's Eternity sits centre-board with the Plasma Caliver Vanguard squads, providing re-rolls on 1s to hit and wound along with persistent Light Cover on one squad. This guy is there to let you constantly supercharge your Plasma and get the most out of your Enriched Rounds, while also giving them (essentially) Armour of Contempt against AP-1 weapons.
** The Programmed Retreat Marshal stays with any squad pushing up the board. The CoV coupled with the Vanguard's -1T in Engagement Range will make them a little more survivable in a frontline brawl, and whatever's left of the unit can proceed to shoot back once they Fall Back on the next turn.
** The Multitasking Cortex Marshal stays with the Skitarii you have sitting on any objective markers. This guy is here to ensure you can score VPs from Actions without leaving one of your 20-man bricks unable to shoot for the rest of your turn.
* Two Archaeopter Fusilaves with Chaff Launchers: These are here to slow down powerhouse units with the Arc Bomb strat and dish out mortal wounds on a 4+ to squads they fly over. They'll also help absorb attacks aimed at mid-board units for a while, with the chaff launchers helping to decrease and can be kamikazed (via Machine Spirit's Revenge) into enemy lines when badly damaged for extra mortals. 
* About 5-7 Ironstrider Balistarii, with 2-3 Dragoons as backup: The Ironstriders are here to do the heavy lifting on anti-armor, since their lascannons outperform the Onager's "Delete This" gun (the Neutron Laser) on pure points-per-damage. The Dragoons are here to achieve midboard control and threaten your opponent's troops (vehicles included) with long-range charges through the Dunestriders strat followed by a charge.
** Depending on how terrain-dense the board is, you may want to swap the Dragoons out for more Balistarii, since it's a pain in the ass to move Dragoons around on a terrain-dense board. Also consider that Ironstriders won't last long in an open slugging match, so play the angle game for all you're worth.
* 5 Pteraxii Skystalkers: These guys are here as objective scorers and harassment units. Drop them from deepstrike onto unclaimed objectives or on your enemy's flanks, then use them to harass their units before they're destroyed/fuck off back into deepstrike. 
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<tab name = "The Tournament Crusher/The Friendship Ruiner">
The core of the best theorycrafted Admech lists revolve around a Lucius Battalion with multiple 20-man Skitarii bricks of Vanguard and Rangers (swap out for either depending on your local meta) and a Mars or Data-Hoard (Auguries) Outrider detachment to slot in Lascannon Ironstrider Ballistarii. Lucius with the multitude of durability buffs they can give to your basic skitarii makes them nigh-unstoppable to just march around the board, gunning down other infantry and even vehicles/monsters if you start investing command points into them, and just literally not dying. Mars/Data-Hoard, on the other hand, pumps up your lascannon Ballistarii to absurd levels of efficiency, giving them canticles or 6++ and re-rolls to hit. Slot in a unit of Infiltrators or a big brick of Serberys Raiders for a spicy Wrath of Mars platform.
*Important to note that you will commonly spend an additional four command points to buy additional warlord traits and relics, and get both the Logi and Artisans Holy Order upgrades. You'll be starting with very few command points, but the pure efficiency this Admech list archetype puts out makes it beyond manageable. 
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