Commence transmission. The Machineel has transcribed the visions blessed unto him by the Omnissiah. The God Machines stir. The enemies of Mars visit eradication on our worlds. It is time. Execute Reclamation Protocols. Awaken the Skitarii. Close transmission.
As a quick foreword, I will address the general structure of my overall Skitarii review. I've elected to cover the Army Special Rules, Warlord Traits, Unique Wargear and Relics of Mars so that my individual unit reviews will be backed by the appropriate context and relevant information without having to constantly explain each as they come. On that note, individual unit articles will be done in the style of my Space Marine character reviews - a trend that will continue with the other smaller codices such as the Cult Mechanicus and Harlequins. I'll be covering the extensive Skitarii armory in two separate articles so as to not clutter this one up too much.
Army Special Rules
Doctrina Imperatives - Every Skitarii model in the codex is subject to this special rule and it stands as one of the most mutable army bonuses imaginable, manifesting as six individual abilities that can each be activated once per game. To use a Doctrina Imperative, you must declare that your entire Skitarii force - even Skitarii featured in multiple detachments - is using one of the six abilities at the start of any of your Movement Phases with the particular one chosen affecting all Skitarii models; the effects of the Imperative chosen will last until the start of your next movement phase wherein you can select another available Doctrine to use. Out of the six Doctrina Imperatives, three are geared towards increasing the forces' shooting capabilities while the other three conversely improve their melee prowess instead; what you must keep in mind is that four of the six abilities do negatively affect the opposite spectrum as detailed below, so choosing to use the more powerful ranged Imperatives (for example) can lead to a temporary but sizable weakness in close combat. To differentiate the shooting and melee doctrines, the former are labelled as Protector Imperatives while the latter are known as Conqueror Imperatives. Furthermore, the three individual abilities constituting each of the two groups are labeled in ascending order as Gamma, Beta and Alpha level to represent their exponentially increasing level of effect upon the Skitarii.
Hazard Optimization (Gamma) - All Skitarii models receive +1 Ballistic Skill. This is the "safe" option to use at the start of a match if you don't want to waste the Alpha level version or suffer any penalties, while it is often enough of a boost to your ranged damage output anyway.
Gundrill Symbiosis (Beta) - All Skitarii models receive +2 Ballistic Skill and -1 Weapon Skill. Seeing as all Skitarii are already Weapon Skill 4 and that most units in the game are either Weapon Skill 4 or Weapon Skill 3 and lower, this isn't much of a downgrade for an army that will mostly be staying out of combat anyway. The increased Ballistic Skill serves to give pseudo re-rolls to the Skitarii' shooting attacks.
Binharic Omniscience (Alpha) - All Skitarii models receive +3 Ballistic Skill and -2 Weapon Skill. The all-out ranged devastation protocol that you will often see used on the first turn of a game provided the Skitarii army in question has the circumstances to favor a strong shooting phase such as exposed squads or optimal ranges and so on. However, being reduced to Weapon Skill 2 is quite the drawback if any melee breaks out given that Weapon Skill 5 becomes a nightmare for your Skitarii units to face while even units such as many of the Tyranid monstrous creatures nearly double their effectiveness in combat. Still, the near perfect accuracy provided by needing 2s to-hit with any failed to-hit roll instead scoring a successful hit on a subsequent roll of 5+ contributes heavily to the Skitarii's high placing in terms of alpha strike potential.
Mindstate Secutor (Gamma) - All Skitarii models receive +1 Weapon Skill. If you are lining up some charges and expecting a few in return but don't feel enough are guaranteed to really warrant the penalties offered by the subsequent Conqueror Imperatives, this is your go-to option. Unlike the Protector Imperatives, using the weaker Conqueror Imperatives first as opposed to the stronger ones is often the best idea given that melee will usually be joined late in the game and shooting is at its most effective in the early to mid game due to inevitable casualties. Also, Weapon Skill 5 sees that your Skitarii will hit nearly anything in the game on a 3+ which is enough for your dedicated assault forces to devastate all their foes and allow your units to hit even Weapon Skill 10 models on 4s.
Technomartyr Concords (Beta) - All Skitarii models receive +2 Weapon Skill and -1 Ballistic Skill. Unless you build your army using almost exclusively Sicarian and Sydonian squads, the meat of a Skitarii' forces' damage output comes from the shooting phase, and turn one charges even for the aforementioned units that possess the awesome Dunestrider special rule are far from guaranteed or even possible in most cases. Ergo, save this one unless you are expecting turn one charges from the opponent or playing mind games such as moving a melee-oriented build up, activating these and daring another melee centric army to charge you in return. The upgrade from Weapon Skill 5 to Weapon Skill 6 is not as significant as it is in the Gamma level Imperatives' alternate case, so keep in mind that this represents diminishing returns against anything that isn't itself an elite assault squad.
Hyperaction Protocols (Alpha) - All Skitarii models receive +3 Weapon Skill and -2 Ballistic Skill. Let it be said that an army of Weapon Skill 7 models can be downright terrifying, but the general mediocre to poor actual damage dealing capabilities of most Skitarii units in a melee ensures that you likely won't get as much out of this as you would expect. However, those Sicarian and Sydonian units I keep mentioning turn into utter monsters with this particular bonus and don't really care about sacrificing their ranged attacks in a turn where even Space Marine characters will learn to fear them. However, I must again stress that the higher a models' Weapon Skill becomes the less important that bonus actually is as most units in the game are already at a lower Weapon Skill value than five, so trying not to waste the incredible shooting phase a Skitarii army can output is critical to the effective use of this Alpha level Imperative.
There are numerous tactical applications of the Doctrina Imperatives, so many in fact that they are highly circumstantial and thus their effective use will be ultimately player-driven; learning which one to use in any given turn is crucial, and while there is a chance of a game going to seven turns, generally you want to use all six of your Doctrina Imperatives before the potential end of the game to maximize the amount of Skitarii units they can benefit. As there tends not to be a general strategy to adhere to with them given how variable games of Warhammer 40,000 can be based purely on which faction you play against among many other factors, I feel some specific tips are more useful here. About the only exception to the above advice is that the Skitarii are predominantly a shooting-oriented army much like their Cult Mechanicus counterparts, so you will tend to use the Protector Imperatives earlier and place greater emphasis on their potential uses while planning out your strategy in a match. In any case, here is what I recommend; against an army that null-deploys and will alpha strike you heavily in the case of a Drop Pod army, consider using the more powerful Conqueror Imperatives against foes capable of charging from reserves as is becoming increasingly common nowadays. Ballistic Skill modifiers do not affect Overwatch or Snap Shots unless specifically stated otherwise so you may as well benefit from the Weapon Skill bonuses to try and beat back any would be chargers, but if you do have available Interceptor shots then rationing out the Protector Imperatives in a manner cognizant with how much Interceptor fire you can muster is also ideal.
On the flip side, if your Skitarii are crashing into the fray in the confines of Allied Drop Pods then using the maximum Protector Imperatives at your disposal would be more beneficial to truly eviscerate the opposition and deal a critical early game blow to their total strength. If you find that your opponents' army is not going to be suffering much damage at all on early turns due to factors such as Night Fighting assisted cover or them sticking to line-of-sight blocking terrain as they advance, use the weaker Protector Imperatives to snag a few extra wounds or hull points while hiding from the inevitable fusillade. If a long to medium ranged bitter duel between two shooting armies occurs, you will need to choose between saving your Alpha level Protector Imperative for when the opponent fully advances into the midfield to claim objectives or throwing caution to the wind and unleashing devastation on a foe in an attempt to cripple them early. Counter to all of that, an army featuring Sicarians and Dragoons could opt to use the weaker Conqueror or Protector Imperatives to dissuade nearby enemies from charging them or alternatively just killing them off anyway, but then unleash the fully powered version of the former to crush any opposition in ensuing melees - Skitarii combat squads are virtually guaranteed to make a melee in turn two! Lastly, you'll likely notice the trend of my recommendations focusing more on the early game; this is an important distinction as the mid to late game scenarios will force you to use Imperatives based more on what is left to choose from rather than what is necessarily the most ideal in a given situation, so choosing to save your stronger ones for a better opportunity to do the most damage is always a viable option as well.
Though similar movement-boosting abilities are popping up in increasing numbers nowadays and we have seen earlier examples with the Chaos Space Marine Maulerfiend in particular, this is the rule that really kick started the trend of adding inches to preset measurements for resolving a models' journey across a tabletop to supplement their base unit type. To this day, it is still the most far reaching of those abilities in terms of how many different areas of positioning it affects and arguably the most powerful as a rule unto its own, though obviously the units it is attached to often aren't comparable to the more recent recipients of those aforementioned copy-cat benefits. To represent the relentless nature of the Skitarii and how surprisingly agile they can be without changing their unit type completely, all models with the Dunestrider special rule add a total of 3" to any move made in the Movement phase, any movement made via a Run action, and to their total charge distance. In the case of an infantry unit that normally moves 6" in the Movement phase, D6" when Running and 2D6" when charging, it will instead move 9" in the Movement phase, D6+3" when Running and 2D6+3" when charging - if the latter two points are at all confusing, simply add 3" to whatever applicable dice roll you make. Not only does this make for near guaranteed charges at short ranged, it massively increases the raw ability to cross the board for any affected unit; rather than taking the usual three turns to get through the 24" no-mans'-land area between the opposing sides' deployment zones, it should instead only take two without having to Run in the second Shooting phase. Given that three of the four units who benefit from Dunestrider are geared towards assault, removing a full turn of incoming shooting from an opponent can be game-changing for these units and really apply pressure to enemies by presenting them with more targets than they would be used to at that time in a match. This should ensure that unless cover intercedes on a villainous spree of care-free indulgence, you will be making incredibly easy turn two charges - or even turn one charges if your opponent advances! All in all, it's a very powerful rule as any person that plays competitive objective based games will tell you; the value of speed is often under-rated and you'll learn to appreciate that once you've been on the receiving end of a properly executed Skitarii Conqueror strategy.
A quick note before we proceed, a Skitarii army is unusual in the sense that its only Warlord choices are squad leaders given that they have no access to Independent Characters inside their own codex. The four eligible options for a Skitarii Warlord are a Ranger Alpha, a Vanguard Alpha, a Ruststalker Princeps and an Infiltrator Princeps; the former two roll a D6 on the Warlord Traits table, while the latter two roll a D3 instead and thus can only ever benefit from traits one, two and three. The first three Skitarii Warlord Traits are mostly personalized to the Warlord itself and provide minor boosts to their combat abilities or durability, and what you will quickly notice is that those types of Warlord Traits are rather poor if the beneficiary is a two-wound virtual clone of its unit. However, the second trio of Warlord Traits are much more useful overall as they provide squad-based or army-wide buffs which a Skitarii army can gain so much from, so if you have a means of re-rolling your Warlord Trait result then make sure to try and get results four, five and six whenever possible.
1) Reinforced Exoskeleton - The Warlord gains the Eternal Warrior special rule. Considering that all characters in the Skitarii army list have at most two wounds and a Toughness value of three with a minimal Feel No Pain roll, there's little to really recommend keeping this Warlord Trait as it doesn't take much effort to a skill such a model. Of course, it's useful for tanking some Strength 6 wounds that the rest of a Skitarii unit may otherwise dread to face, especially for a Princeps in a Sicarian unit.
2) Artificer Armament - The Warlord benefits from Master-Crafting on one of its' weapons, not including any relevant Relics of Mars. This is a cute little bonus for one of the standard infantry squad leaders given that they can only really add pistols and special melee weapons to their stock repertoire, but it is of slightly greater use on a Princeps.
3) Masterwork Bionics - The Warlord can re-roll failed Feel No Pain rolls. I actually don't mind this trait given that an armor, cover or invulnerable save followed by a re-rollable Feel No Pain roll can make for a fairly survivable leader of an army against small arms fire, but only for a Princeps (again) as a 6+ roll on an Alpha just won't cut it here.
4) Incense Generatorum - The Warlord gains the Shrouded special rule. Conferring +2 to eligible cover saves is an impressive defensive bonus for any unit in the game, especially considering that it can be used to grant a squad a 2+ cover save while still maintaining full firing effectiveness depending on the terrain utilized. Additionally, benefiting from a 5+ cover save in the open allows a Skitarii group to advance with much more surety given that they also get to use their Feel No Pain (6+) rolls in conjunction with the cover saves.
5) Disciple of the Omnissiah - The Warlord and all friendly Skitarii units within 12" re-roll failed Morale, Pinning and Fear tests. Seeing as Skitarii are universally Leadership 8 or Leadership 9 and are susceptible to all three of those aforementioned effects, this is a fine trait for keeping a Skitarii force in the battle and taking or holding objectives as necessary.
6) Emotionless Clarity - The Warlord and his unit fire Overwatch at Ballistic Skill 4. Seeing as both Rangers and Vanguards are incredibly powerful budget price ranged squads that pack a mean punch with both their basic and special weapons, this is about as nasty of a charge-defence as you could want given that both units tend not to want to be in an assault unless absolutely necessary. A very powerful ability as any Dark Angel player will tell you.
The Omnissiah welcomes your admission. The Machineel deciphers its will. Venerate the Machine God.