The TIE/WL Walker, affectionately called the TIEtan by pilots, is a collaborative project between Sienar Fleet Systems and Kuat Drive Yards. When the Imperial Military's R&D labs approached the two contracted manufacturers with a common project seeking to merge the strengths of the TIE series of starfighters with the AT series of walkers, representatives of the two companies were hostile to the idea at first, but eventually an agreement was reached.
The Walker doesn't only carry the TIE name as a nod to its design, as it is indeed powered by a dual Ion-based power core. The design brief called for a ground vehicle with the versatility of a walker, but with the maneuverability of a starfighter. Unlike any AT series vehicle, the TIE Walker was designed to be roughly humanoid in shape, featuring legs that had far greater range of motion than any AT model. One very clear and obvious advantage the TIEtan has, for example, is that it can get back up if knocked over. The design process of the vehicle was long and troubled, primarily due to constant workplace incompatibility between the Sienar and Kuat staff.
The TIEtan, in spite of being the result of the concept "mix the TIE with the AT", differs from both in many aspects. It is the sole Imperial military vehicle which has a primary weapon system independent of the main vehicle itself. The large gun is held by the machine's humanoid hands instead of being integrated. It also represent the complete opposite of typical Imperial design directives - instead of a simple machine that is easy to mass produce, and is therefore expendable, the TIEtan is a highly complex feat of engineering, and each unit is extremely costly to produce, thus the retrieval of even heavily damaged units is imperative.
The TIEtan's main gun also went through many design iterations. The weapon is loaded with three different kinds of ammunition, which already alludes to another major difference from typical Imperial weapons - instead of being a blaster, the WLG-108 uses projectiles. The basic loadout includes independent magazines for hybrid Anti-Material/Armor Piercing ammo, High-Explosive ammo and Incendiary ammo. Sienar and Kuat engineers argued during development extensively whether to settle with incendiary ammo or give the Walker an actual flamethrower with a back-mounted fuel tank, however eventually the danger of the fuel tank caused the incendiary ammo to be the final version. With the back-slot freed up, R&D teams explored the concept of a dedicated melee weapon, and produced a working prototype for a huge chain-sword. In the end, the weapon would have demanded significant downgrades in other areas to fit the budget, so it was scrapped. The design team's progress report about the cancellation of the melee weapon stated "The Walker can punch anything in melee range anyway".
Eventually the back-slot was designated as a storage area for the WLG-108, allowing the TIEtan to use its dextrous hands for support activities, like clearing debris before less agile vehicles, like AT-STs and Sabre tanks. After the Walker was deployed, resourceful pilots also discovered that the hands can be used for climbing.
Additional armaments include an auto-targeting anti-infantry "cleanup" blaster mounted on the top of the cockpit, a "small" (compared to the WLG-108) hand-held blaster sidearm should primary ammo run out (stored on a hip-holster) and a 4-missile extendable launcher bank suitable for anti-air and anti-material applications.
The humanoid design of the TIEtan allowed for a considerably wide range of motion, almost equal to that of humans. Most standard vehicle control schemes limited this ability, however, so the design team had to explore alternate options. Motion-controls were considered, which saw pilots dressed in an exo-skeleton with sensors on all their joints translating their own movements to the vehicle, however this would have required far too much room, which the cockpit did not provide. The designers were forced to opt for a highly experimental and costly method instead, which they dubbed Spinal Bypass. TIEtan pilots have to be extensively implanted with special cybernetics, primarily in their brains and eyes, but the biggest procedure with the complete replacement of the entire spine with a cybernetic augmentation. This implant is then used to "plug-in" to the TIEtan, and the brain implants redirect electrical impulses from the brain to the vehicle. When the pilot "moves" their hand, the signal never reaches their actual hand, but is instead directed into the Walker, so it moves its hand. While in the cockpit, the pilots are temporarily paralysed. The cockpit contains basic controls, but these are only there due to the value of the vehicles themselves - should a TIEtan pilot be incapacitated, but the vehicle is still operable, non-implanted Imperial personnel can access very limited functionality, allowing them to walk the Walker back to base.
Due to the much wider range of motion and higher speed compared to other walkers, during simulations veteran TIE pilots fared much better than AT pilots, thus the pool of high-performing starfighter pilots is where TIEtan pilots are transferred from and trained.
Since piloting a TIEtan is a sensation equal to moving your own body, many pilots developed motorfunction quirks after spending a lot of time out in the field. As the Walker possesses no "head" and the cockpit is in the torso, the pilots never move their necks while inside. After prolonged missions, many bring this kind of motion with them to down time. When someone calls out to a TIEtan pilot, instead of glancing over, they would twist their whole torso to face the other person. This has resulted in a marked increase of personnel problems and bullying towards pilots, who tend to keep to one another for company. As a result, the HR department of the Imperial Military prescribed mandatory 3 hours per week with base counselors.
TIEtans didn't see much field action during the early days of the Empire, and due to their cost they never became widespread, always remaining elite units of few number. Though extensively field tested prior, a unit consisting of 6 TIEtans were first properly deployed during the Battle of Hoth. While the standard Imperial units, consisting of AT-ATs and AT-STs lead the main assault, the Walker unit was sent to traverse the mountains and snow-dunes hiding the Rebel airfield. Though many Rebels, including all high-value targets escaped, the TIEtans performed admirably in the extreme weather conditions, broke through the defenses and shot down several smaller Rebel ships. They were later deployed across many theatres of war, and also used as intimidation in newly "liberated" regions - however, this secondary function wasn't often used, as 20 AT-STs are scarier to farmers than a single TIEtan, but they still cost less. Walkers modified for zero-g operation patrolled the outer hull of the Death Star 2, for example. Following the fall of the Empire, the remnant could no longer afford manufacturing new TIEtans, so those which remained in operation became extremely important, and their pilots became celebrated legends among the military. It is unknown whether the First Order is attempting to adapt the old TIE Walker design for their own use, but so far they have not fielded any similar vehicles.
