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

===Fast Attack===
*'''Ironstrider Engines:''' The Ironstriders garnered a bit of controversy during the codex's release. Because they were somehow labeled {{W40kKeyword|Core}}, this meant that they could benefit from a lot of things, including buff auras and certain stratagems. The July errata neutered this a bit by removing them from Core, but their firepower remains just as potent as before.
<tabs>
<tab name="Ironstrider Ballistarii">
*'''Ironstrider Ballistarii''': Your mobile backfield and occasionally midfield anti-tank/elite sniper of choice. The new codex has given them extremely good buffs in the sense of adding +1 to their saves, +1 shot for each of their two auto cannons, and 3+D3 damage on their lascannons. Cheap, deceptively durable when need be in a Mars, Lucius, or Data-Hoard detachment, mobile, and able to output unfair amounts of damage, which makes these a top tier threat in the new Admech codex. Get them while they're hot before the guaranteed price hike.
**Lascannon Ballistarii are absolutely beyond disgusting right now when run in a Mars/Data-Hoard (Auguries) Outrider detachment. Not only are they severely undercosted for their damage output, but taking them in small squads of 1-3 makes them immune to morale since they're Ld8 and allows a very efficient usage of the Mars Dogma to re-roll 1 hit roll per unit and the canticle for them to re-roll a hit, wound, and damage roll (if you use Data-Hoard, instead you just need to get within 24" to get full re-rolls to hit, but you don't get the once per game Dogma). They are extremely mobile and play as one of the most threatening backfield anti-tank snipers in the entire game, and if need be, can run out into the center of the board when you've mopped up anything that can threaten them. They will most certainly be nerfed in the near future, as they are extremely undercosted at 75 points a pop for two D3+1d3 assault lascannons. Play the angle game with them. Peek them out to get a bead on any armor threat, and they ''will'' kill it. 
</tab>
<tab name="Sydonian Dragoons">
*'''Sydonian Dragoons''': Received a similar buff to what its ranged cousin got, giving it +1 to its save characteristic, and the -1 to be hit from its incense clouds also work in melee now. Gaining a point of AP on their taser lance to make them S8 AP-2 D2 and a stratagem to make their taser weapons explode on 5s and 6s, it seems that the new codex has listened to the anguished cries of all Dragoon enthusiasts who had their melee chickens gutted in the transition to 9th edition. Now cheap as chips at 50 pts a pop (+5 for the Taser Lance), they may actually see the tabletop!
</tab>
</tabs>
*'''Serberys Riders:''' The reigning champs of the skirmishing department. Not only are they very fast, but also pack a powerful punch and can do so while being able to hide behind cover.
<tabs>
<tab name="Serberys Raiders">
*'''Serberys Raiders:''' Serberys Raiders are Skitarii Rangers that are mounted on cybernetic dog-mounts. T4, 2W, and a new 5++ Invulnerable save make them a bit of a sidegrade coming from the old codex where they had lost a wound. Nevertheless, gaining a point of AP on their carbines still puts them into one of the best Fast Attack choices in the Adeptus Mechanicus 9th edition codex. They can do it all. A 12" pregame move is extremely handy in the hands of a skilled player, able to set up early board control before the game has even begun. Charging them can be a nightmare due to their stratagem that allows them to immediately make a move if they become the target of a charge, and they can target characters with their carbines and deal mortals on 6s to wound as they are snipers. There's practically no downside to at least taking two small units in your list. They're fantastic screens and harassers, and with certain combos, can actually output respectable damage.
**If you really want to meme it up, take two units of nine of these guys in a Mars detachment, pop Wrath of Mars, and delete any character you see hiding behind their army if you manage to get in range. Wrath of Mars makes them deal mortals on 6s to wound, which they also already do because they are snipers. That's right. ''Two mortal wounds for each natural 6 to wound''.
***Remember to keep tabs on your mortal wounds separately if you do this - once the stratagem has dealt 6 mortals it can't deal any more, so if you manage to roll 7 or more 6s to wound (which is ''extremely'' unlikely), each 6 to wound past the 6th only deals 1 mortal.  In actual practice, doing this with 8 galvanic carbines (i.e. 16 shots) on the same turn you are applying Benediction of the Omnissiah and the Protector Imperative will usually inflict 5.242 mortals on anything, 4.326 if you're BS3+ (e.g. from taking the penalty to Advance).  Getting the alpha into range is of almost no benefit, getting you from 5.242 to 5.525 or from 4.326 to 4.547.
</tab>
<tab name="Serberys Sulphurhounds">
*'''Serberys Sulphurhounds:''' Fast-moving Skitarii Vanguard gunslingers riding cyber-dogs that breath fire. Identical in statline to the Raiders, but with different special weapons and rules. Basic models are equipped with dual phosphor pistols (same stats as the Phospor Blast pistol but strength 4 instead of 5.) as well as a sulphur breath (same stats as the phosphor pistol, but 12", Pistol D6, and auto hits.) The Alpha carries a single Phosphor Blast Pistol and a power maul, neither of which can be swapped out. Finally, one model can swap a phosphor pistol for a Phosphor blast carbine (24", Assault 4, strength 5, AP -1, 1 damage with all the usual phosphor rules). Their Pistoleers' special rule allows them to advance and fire pistols, and they share the rad-saturation rule with the Vanguards.  As with the Serberys Raiders, the Sulphurhounds are a skirmisher unit that is cheap, though not as cheap, fast, character sniping or ranged as the raiders.
</tab>
</tabs>
*'''Pteraxii:''' Another unit that was the center of attention due upon the Codex's release. The Booster Thrust Stratagem RAW allowed them to immediately jump back into reserves after landing out of them, making them nigh-untouchable. With the errata breaking this option over its knee, the pteraxii are back to being glass cannons - Booster Thrust now can't target a unit that was deployed this turn.  Otherwise, it's a stratagem all Pteraxii share, to, at the end of your turn, jump back into reserves and be forced to deep strike back onto the table on your next turn.
<tabs>
<tab name ="Pteraxii Skystalkers">
*'''Pteraxii Skystalkers:''' Flying drop troops that vomit shots. They have a special stratagem, Arc Grenades, that lets them supplement their friendly Shooting phase shooting with spending 1 CP for, on average, 2 mortal wounds to a {{W40Kkeyword|vehicle}} within 6", but actually a 1/6 chance each of 0 and 2d3 and otherwise 1d3, so it's very swingy for something as precious as a CP.  They can shoot after falling back, which is why it's so stupid the Alpha trades an 18" assault gun for a 12" pistol.  Their ranged output is 5 S3 shots per dude, and their melee output is taser goads on everyone.
**Expect your opponent to blow them out of the water the turn after they drop - they're fragile glass cannons, and no savvy opponent will let them live.
</tab>
<tab name="Pteraxii Sterylizors">
*'''Pteraxii Sterylizors:''' Close range Pteraxii, with a 12" Flamer that ignores the cover bonus (that's in deep strike range). Then if they charge, they each make 3 S4 AP-1 attacks, and the Alpha makes 4 S6 taser goad attacks. Unfortunately, the alpha is forced to carry a substantially worse gun than the rest of the unit - it'll land fewer shots at worse S and worse AP, and that's assuming you can shoot it, as it's the only model in the unit that can't shoot after advancing.
**2pts more than infiltrators for an AP -1 flamer making their firepower equal to infiltrators - these are glass cannons like skystalkers, don't expect them to survive to fly off again or have a second shot - I'd stick with your infiltrators for efficiency, but it's close.
** With the Deeply Sunk Talons stratagem to stop a fallback on +2, they can have both survivability and suppress enemy non-flyer tanks/artillery. It can be kept in combat for the next turn and if the enemy you were engaging is no longer important, you can make it soar to the skies, even if stuck in combat range, to descend in deep strike the next turn.
** For 2ppm more than Skystalkers, there is a lot to recommend them. Even if you want to use Wrath of Mars on one of the two units, Sterylizors get more hits out of deep strike without having to spend additional CP or coordinating a Dominus/Cawl to be within aura radius (d6 auto-hit averages more hits than 5 shots at 3+). Add the fact that you can survive a bit longer using Deeply Sunk Talons and have way better melee and the answer to the "what should I build my box of Pteraxii as?" question is pretty straightforward.
</tab>
</tabs>