The Railguneer is the upgraded version of the Lancer once upgraded with a Nanofiber Sync. Although they lose the ability to garrison structures, their plasma railgun can make short work of vehicles, including heavier ones, though less so against structures, and their bulkier armor improves their durability at the cost of some mobility.
What's worse, Railguneers are completely uncrushable and no longer susceptible to EMP, making them a dangerous threat to virtually any vehicles.
The Lancer grows stronger when exposed to the Nanofiber Sync, and becomes the Railguneer - a powerful force that the experienced tank operators will avoid at all costs. The nanofibers enhance Railguneers' cybernetic limbs, making them capable of carrying a heavy armor design, which encompasses this warrior's body upon the Sync. The armor makes a Railguneer immune to getting crushed by the largest of tanks, but also has self-sustainability systems, which will negate the effects of EMP weapons.
Railguneer's biggest attribute however is its weapon, a personal plasma railgun which gives them an edge over the Lancers' in battle: where Lancers could not reach with their short-range pressurizer lances, the Railguneer will fire from a distance. On the other hand, the weapon's effectiveness against structures or infantry decreases in comparison to the Railguneer's original form. That is after all, the very nature of the Sync: to gain a thing, while discarding another in return.
In the event enemy vehicles may be too difficult to eliminate for Lancers, the Railguneers will solve that dilemma almost instantly. These hulking soldiers redefine the term 'tank destroyer' into a whole new meaning - their portable Plasma Railguns are among the most powerful infantry based anti-vehicle weapons in the game, capable of destroying main battle tanks in matter of a few shots.
The Pressurizer Lance wielded by the Lancers have a short range, which renders them vulnerable to units that can kite them easily. Railguneers do not have this issue as their issued weapons have superior range (twice that of the Lancer's), putting them on par with the majority of vehicles with the exception of artillery units. If the range increase wasn't bad enough news for Foehn's enemies, the Plasma Railgun is also much stronger than the Pressurizer Lance - groups of Railguneers can easily hold their ground against Tier 3 tanks and often emerge as the victor, provided they aren't overwhelmed with sheer numbers. If loaded in a Jackal Racer, Railguneers become the ultimate hit-and-run anti-vehicle unit, though his advantage of durability against dedicated anti-armor weapons will be negated.
Railguneers, while feared forces that no vehicle would ever want to face in a direct confrontation, do have their inherent drawbacks. While the Lancer is a fleet-of-foot soldier that can run faster than conventional infantry units, their evolved versions aren't, given the added weight of their armor and weapons. This reduces their effectiveness against sudden armored attacks as they won't be able to mobilize as quickly. Their Plasma Railguns are also not effective against infantry and structures, thus limiting their roles as almost pure anti-tank infantry. While their large amount of health will allow them to survive more punishment, they are still inherently vulnerable to anti-infantry weapons. One important thing to note is that even though they can't be affected by EMPs, magnetic weapons can still pin them down and render them immobile. Last but not least, Railguneers cannot be trained directly from the Foehn Barracks, being only accessible via the Nanofiber Sync support power.