The Imperial Chiss armada is the primary antagonist faction in Invasion of Skyrim. They're loyal to Grand Admiral Thrawn, and will stop at nothing to see his victory on Nirn come about. As such, they are largely dangerous fanatics who give their lives freely in Thrawn's name. They come in a variety of different classes, from invisible Rogues to brutish Tanks.
The Imperial Chiss armada is the force that Thrawn arrived on Skyrim with, and the force he wants to leave Skyrim with. They are numerous, but limited. Reinforcements cannot arrive from off-planet, as all communication and transport was mysteriously severed shortly after original landfall. Instead, they recruit locally, often conscripting bandits and other outlaws to do their dirty work for them. When that fails, however, they will step in personally to see the objective is completed.
The Imperial Chiss armada is a terrifyingly large and complex entity, made up of many different clans, ranks, status, and more. However, they can be divided into four easy categories for quick reference.
Imperial Chiss units[]
Conscripts/Traitors/Thalmor[]
These units are generally weaker, and not even Chiss in race. They are generally natives of Skyrim who think they're working for the right side, or are just evil individuals themselves. They are often seen in large numbers, commanded by a slightly higher ranked individual such as Thalmor or Imperial/Stormcloak sergeants, or by actually Chiss units.
Although weak, under strong leadership, these taskforces can be very dangerous. They often wear light armor, and do not receive the regular Chiss armor until much later in game.
Soldiers/Archers/Mages[]
The bread and butter units of the Imperial Armada are dangerous and well armed. They have strong weaponry, often enchanted to match their specialty, and possess great skill and prowess in battle. Soldiers are easily identified by race, as they are generally Chiss. There are a few non-Chiss soldiers that have ascended the ranks, such as the Beastmaster, Spy, or Mechanic units.
Chiss Soldiers have many tiers of armor, each escalating in strength compared to the last, and usually coming in light and heavy variations. These armors can come with incredibly powerful enchantments attached to them, known as "Strength of Csilla" enchantments. Soldiers with these cuirasses are insanely difficult to fight, and should only be fought with Resistance squadmates nearby.
Elites[]
Elite Soldiers are the most feared enemies in all of Skyrim. These units are immediately identified by their stark black, green and red armor. They are extremely skilled, often capable of taking on five or more enemies at a time, and come in a variety of classes. They are all agile and skilled in magic, oftentimes blending the classes together. Some soldiers can heal large groups of allies, while mages may possess incredibly powerful close-combat weapons.
Elites bend the rules of reality, oftentimes performing shocking actions that a player could never perform. They are the strongest Non-Image Chiss unit in Invasion of Skyrim, and should be treated with extreme caution.
Dragon Knights[]
A seperate class has cropped up, known as the Dragon Knights. These Chiss wear the bones of Dragons they've defeated, and are impossible to classify as anything other than extremely dangerous. They are incredibly rare units that should often be avoided. as they wield strange magic and powerful dragonbone weapons.