Shadows

Despite their codes of honour the Aktangsi are tricky and ruthlessly practical when it comes to warfare, playing to their natural strengths, shown best by these troops. Technically referred to as Aktangsi Shock Troops, in reality most people just refer to them as Shadows. A good translation to Standard would be Guerillas or Black Ops.

Composition

Manpower

A typical Shadows squad will have a dozen members. Two leaders analogous to a Captain and Lieutenant, two scouts, two who double as medics, and the rest soldiers. Though many missions Shadows go on are blackzones communicatoin wise, there will ususally be one or two with communication equipment for emergencies either way, including requesting emergency backup or extraction, or other soldiers warning them of something about to go down in the area.
Ideally, squads are formed during training and remain for the entire length of their tours, but in reality, the death count for Shadows is so high that squads are frequently split, merged, and shuffled to ensure all roles are filled for active shadows. Usually there will be multiple squads in an area, spread out but close enough to offer emergency support to each other if required, and allowing co-ordination of efforts.

Weaponry

Shadows are mostly equipped with weaponry designed for closer combat, and are one of the only formations in the BDA military to use melee weapons as a primary instead of a secondary or backup. Every Shadow carries a blade with them, one designed more for puncturing and stabbing than slashing, and the majority also carry close-range projectiles, similar to pre-warp Terran pistols. Several in a unit will also carry grenades of various kinds, usually shrapnel, smoke-and-scent, or EMPs.

Vehicles

Shadows do not generally use vehicles once on the battlefield, preferring to move on foot as it's much stealthier. However, all will recieve training to use single-use light overland vechicles, and it's normal for one or two to have some sort of pilot training, formal or otherwise. These sorts of vehicles are used for getting to or being extracted from wherever they've been sent to fight, or getting from the site of one alertcation to another in emergencies.

Structure

Officially, a Shadows squad has a leader, a second-in-command, and that's it. Either are able to request assistance from other Shadows in the area, and the leaders are able to order assistance from other units in the area, many of whom are not allowed to refuse on their own but must ask their Commanders if it is viable. Squad leaders get their orders from Commanders who are off the field of battle and can only take orders from them, though other units can request their assistance from the Commander if needed.
However, in reality, the chain of command tends to get a bit loose when Shadows are out on assignment. With everyone tending to have slightly different specialisations, the leader will sometimes struggle to retain control over the entire squad or even voluntarily hand over command in some situations, despite that being against protocol.

Tactics

Shadows are often understood more as commandos or special forces by other species. However, in function they are traditional Shock troops, being created to lead an attack on a larger force, specialised in mobility and piercing assaults, and expected to take heavy casualties even in successful operations. They are used to break enemy formations and weaken them, as well as often steering enemy troops towards where large amounts of Aktangsi infantry wait to take advantage. It just happens that they're also usually stealthy and hard to pin down. 
Most Veilwalkers drafted will be pushed to become Shock troops, which is why they have such a terrifying reputation. Horror stories abound of knife-wielding Aktangsi emerging from thin air and leaping from someone's shadow to gut someone before disappearing again as swiftly as they arrived, continuing to harry them and pick away at their numbers as they grew twitcher and more desperate, until they ran a corner to see thirty more Aktangsi pointing weapons straight at them.
Unsurprisingly, while this tactic isn't very effective against Odari it is very effective at getting anyone else to surrender from sheer terror and exhaustion - and, despite their bloody reputation, Aktangsi soldiers have some of the lowest overall kill rates due to the high level of surrenders.

Training

All Shadows undergo intense survival and stamina training, as they will often be moving on foot through hostile environments and have to remain agile. They are also given advanced melee combat training, as infantry troops are expected to mostly remain at a distance and rely on firearms and grenades.
Many are also cross-trained, mostly because of what they did on their previous tours. Apart from specially trained medics, scouts, and leaders, it's fairly common to speak to a soldier who's a Shadow and find out they have a pilot licence or are an engineer or something of the like. There tends to be a certain level of in-the-field cross-training going on as well as they share skills to reduce the chance of a single point of failure.
After finishing an entire tour, Shadows have mandatory maintenance training for two lunar cycles to polish up any rough edges they inevitably gained over the course of active training and reinforce the chain of command.

Logistics

Logistical Support

Shadows are the elite troops of the Aktangsi and the best shock troops that the entire BDA has, and therefore receive a lot of logistical support, much of it transport based. Shadows have their own dedicated transport divisions to get them in and out of areas when needed, and a dedicated quartermaster division.

Auxilia

While Shadows broadly do their work on their own, they are able to more or less order order other units around, especially infantry, and request air support or artillery if necessary. In these cases the Shadows are like the dogs chasing their prey toward the men with guns, getting them out of where they're dug in or hiding to expose them, or corralling them somewhere where they're much easier to kill or force to surrender.

Recruitment

While all Aktangsi go through a draft a few years into adulthood, the vast majority of Veilwalkers drafted end up as Shadows. Recruits must have already been through basic training and spent at least one tour as general infantry in order to be moved up to the Shadows. While technically it is possible to refuse a request to be moved up to the Shadows, many commanding officers will deliberately make their lives hell if they try, and their peers are advised to try and encourage them to take their rightful positions.

History

Perhaps the most famous use of Shadows in recent years was on Trilik III, an ice moon and base of operations for the Raktajanta Hunt. Eight squads were sent there as part of a major operation to remove the Raktajanta from the moon. They suffered catastrophic losses even for Shadows, with a 97% casualty rate due to only three survivors making it off the moon. They all required extensive hospital stays and psychiatric help and were honourably discharged after being found no longer fit for duty.
The decision to send ectotherms to an ice moon and use their low temperatures to hide their presence has been widely criticized and investigations were opened, though ultimately no upper command was ever severely reprimanded. While on the BDA side many rumours and questions have continued about the events planet-side, for the Raktajanta it was not only a humiliating defeat but a terrifying one. Less than a quarter of their stationed troops made it off-planet, with a number being slaughtered as they fled for the ships or even once they made it onboard by freezing, starving, delirious Shadows. Even years after the events that went down there, Raktajanta still tell horror stories about the Beast of the Tundra.
It was a complete bloodbath on all sides, and nobody is going to forget it for a while.

Type

Shock

Overall training Level

Semi-professional

Assumed Veterancy

Experienced