AOTTG: Final Legion

Chapter 0 The Lore

The Year was 1200 when they appeared

Abominations sent from the depths of Hell as what all Religions stated at that time. They don't sleep, nor have the need of sustenance in order to keep moving. It seemed like their only goal was to eradicate all of Humanity.

Humanity before it fell fought each other. Remnants of old Empires and Rising new ones took advantage on anyone they seemed worth conquering. Then, seemingly out of nowhere, the Demonic Humanoids appeared out of nowhere somewhere in the Continent. One by one, Kingdoms fell, until the remnants of an old Empire which once united the Continent, retreated to an Island they called Hibernia in 1213, taking with them all the books of all Libraries within their reach. All knowledge must not be lost. They built 3 walls to protect themselves against the Incoming hoards of Titans. Eventually, Humanity outside the walls seemingly disappeared in 1216

Hadrian's Wall, built by the first Emperor who came to govern the Island in 1220. The massive project took 3 years to build the 1603 kilometer (996mi) long wall. It featured tall towers, wide ramparts, moats and the Imperial Government's then main weapon to fight the Titans, the inextinguishable flames, Red Flame  (reference to Greek Fire), which was a large Flamethrower that shoots out flames that can't be extinguished even underwater.

Anastasian Wall, built by Empress Anastasia during her reign in 1280. The young Empress saw that if a breach on the walls were to open, humanity would be doomed, and thus, began a project to build another set of walls stretching up to 840km (522mi). It had the same features as Hadrian's Wall, but with the absence of a Moat and the Red Flame defenses.

Theodosian Walls, the Biggest Walls out of all of them. It was over 287km (178mi) long, was massive and have deep moats, as well as the Red Flame defense, It featured large towers, Advanced Cannon Defenses and had 2 Gates. It also had an Underground Canals, aqueducts, and a rumored giant mirror which uses the Sun's light to melt anything that may breach the walls, although these are just rumors. Emperor Theodosius built these walls thinking that the Capital must have it's own defenses in case the two walls fell, and underwent another massive project in 1315 that nearly bankrupted the Empire. Eventually, the project was completed after 2 years.

300 years after Humanity isolated itself, a new discovery has been made which evened the odds against these Titans. The Omni Directional Maneuver Gear (ODM Gear), which allows the users to hook, reel in and out of harms way, all the while maintaining momentum through the use of a Gas Accelerator. Blades made of Crucible Steel were produced as the main weapon to combat Titans. The blades were attached to the handle, as well as  the maneuver controls. A small wire connected from the hilt of the handle all the way back to the structure of the ODM Gear, which was a small piece of contraption weighing about 15 kilos. Boxes acting as scabbards, containing around 4 blades, as the blades were designed to snap upon contact with bone.

With this invention, the Military took on the offensive and decided it was time to venture further out of the walls. No longer must they rely on the defenses of Hadrian's wall to fight the Titans, as they have the ODM Gear. Several scouting parties were sent but no large scale operations were conducted. The more they combat Titans with the ODM Gear, the more Military Experience they gained, paving way for innovation in tactics and technology.

Thus, the Military reformed itself. No longer was the Military considered as "Wall Guards", but rather was reorganized into a much more professional, organized and specialized ODM branches.

Ripensis (Auxiliary)

-Support Elements of the main Army. Often regarded as the most important Branch of the Military, as they handle Wall maintenance, Military Logistics, Disaster Response and Auxiliary Support. They handle Supplies and Medical Support to the main army, although this does not deprive them of the ability to attack titans as they are still considered to be very skilled in their ODM Gear

Imperial Guards (Guardsmen)

-Regarded as the main military force that focuses more direct combat with Titans. Due to their main role in combating Titans, they're usually associated with Anti-Titan Weaponry like Cannons and other Prototypes. They are the main Army of the Imperial Military and is also in-charge of Crowd Control, Anti-Rebel Suppression and establishing control over Infested Territories outside the walls

Venators

-Often referred to as 'City Guards'. They are assigned as a Security Unit in Cities within the walls, or abandoned settlements or Outposts outside the walls, and is tasked in protecting vital points of interests. Due to their constant  exposure to Titans, they are mostly regarded as the most experience Branch in the Military. It is said that majority of the Cadets who graduate the Academy are assigned to this Branch as they constantly lose much of their forces to Titan Engagements

And thus, with these reforms, our story begins. The year is 1450, and humanity is willing to take one big step outside its walls...