Deep Wardens Legion
"The Deep Warden Legion is made up of the very bravest, strongest, and most expendable soldiers the Empire has to offer." -Madam Lazoya of the Oshamni Senate, (elder mermaid)I always was impressed by the concept of the Night's Watch from George R. Martin's Song of Ice and Fire series and I thought something similar might work for my world because of what Void demons represent, but it is not practical for Scarterrans or Scaraquans to build a giant wall that covers the entire north and south poles from sea to sky. Void Demons do not need to breathe. They can fly, run, or swim and they can enter the mortal plane from anywhere on the poles. Scaraqua, at least for the Sea of Enosha (circled in purple) which has the natural choke point of the appropriately named Demonic Strait (circled in red). The Sea of Enosha is the mostly densely populated undersea realm in all of Scaraqua, so many forward Demons would like to attack it. Most Void demons that have the idea attacking the Sea of Enosha, will usually enter via the north pole and try to swim through the Demonic Strait. Void Demons can try to fly over the land near the Demonic Strait for hundreds of miles of land and then dive into the Sea of Enosha, but in most cases they will get distracted and choose to attack Scarterra instead. Thus, by fortifying the Demonic Strait, the Oshamni Empire can avoid most but not all random Void demon incursions, which is part of the reason the Oshamni are so prosperous and powerful relative to the other undersea nations. They don't have their lives disrupted by random Void incursions half as often as the other undersea nations. The Deep Wardens Legion is the Oshamni's first line of defense against the Void.
Currently, the order has roughly 1200 members. ~400 soldiers, ~800 support staff, ~20 mages and theurgists. Because fighting demons doesn't simply imperil one's life, but it imperils one's very soul to a possible oblivion, there are not a lot of volunteers. Criminals can get a pardon for past crimes if they join the Order. Paupers can be guaranteed money and food if they join. Thus most, but not all of the legion's members are the castoffs from society. Unlike most conventional legions, the Deep Wardens Legion is fully integrated with all known undersea races serving in the same unit. Astalakians regularly fight side-by-side with Merfolk, Ojiongo, and even a few Karakhai. The legionaries are united by their grim task and this sense of desperate camaraderie helps overcome the normal fiction between the assorted Scaraquan races that makeup up the Oshamni Empire.
The legion is focused on mobility first and foremost, so they do not carry heavy equipment. They are well equipped with temporary magical items, magical tiles and other potion equivalents for augmentation, healing, and signaling.
Most of the legion is trained in spears and long daggers just like the regular legions and have comparable armor. The legion has some magical weapons enchanted to be extra harmful to demons that are highly valued treasures of the legion.
Total obedience to superiors is mandatory, but soldiers are expected to display imitative and be able to do their duty without constant supervision. Promotion is based on merit and unlike the other legions, politics or race rarely plays a major factor in who gets promoted and who does not.
The Demonic Strait is fairly narrow on the whole, but a few places are extra narrow, some of them have been built that way artificially with construction. In the event of an incursion, the Legion will make a temporary stand at each chokepoint, then flee to the next chokepoint if the they meet too much resistance or the Demons decide to take to the air temporarily to go around the choke point The Legion has permanent watchmen at each choke point plus they have regular patrols swimming up and down the strait. The entire strait is lined with acoustically amplified virdilut tubes that allow outposts to communicate with taps similar to Morse Code in the real world. If the tubes are damaged or otherwise temporarily inaccessible, the watch men and patrols carry the magical equivalent of underwater flares as a backup means of communication. Thus, the Legion's watchmen call for reinforcements quickly in most circumstances. The strait is also lined with hidden supply caches. Given that Void demons have poor eyesight for spotting non-living things, it does not take a lot of effort to hide hide a cache of potions or weapons from hostile Void Demons.
Training is intense but somewhat informal. New recruits are vigorously trained in combat, reconnaissance, field medicine, and fast swimming drills among other things.
The waters of the demonic straight have some modest mineral resources but the area does not support many plants or fish, so foodstuffs and medicinal supplies have to be imported regularly. Most of the farms at the mouth of the Demonic Strait do a large portion of their business with the Deep Warden Legion. Sometimes, the Legion will trade with barbarian tribes swimming north of the mouth of the Strait.
If there is an unusual upsurge in Void activity, the legion can call in reinforcements from the regular army, but in most cases, such reinforcements are slow in coming.
The soldiers get the half again the normal payment legionaries receive as hazard pay, even if their skills are somewhat subpar. There are very few exploitable resources in the Demonic Strait, so most of their supplies have to be imported.
Even with the relative high salary given to the soldiers of the legion, it is difficult to find volunteers willing to risk the destruction of their very souls. The Deep Wardens Legion cannot afford to be picky with recruits. Whereas most legions have a roughly even mix of males and females, it is noteworthy that the Deep Wardens legions skews heavily male, roughly three-to-one. Most of the recruits are criminals who join the legion to receive a pardon. Others join the legion to avoid abject poverty. A few are extremely patriotic or have very deep settled spiritual beliefs that they are willing to risk their souls for the greater good without coercion. A few are nihilists who either don't believe in the afterlife or they don't believe they have a positive afterlife coming. Members of other legions are occasionally rotated into the Deep Wardens legion for a temporary basis, usually as part of a punishment.
Given that the heartland of the Oshamni Empire is in the Sea of Enosha, they quickly realized that it was in their interest to fortify the Demonic Strait. Originally they rotated their regular legions in and out of the Strait, but they had a large problem with soldiers deserting. It is one thing to ask a soldier to risk her life in defense of the realm, but it's another to ask her to risk her soul to oblivion. There were experiments with giving legionnaires in the Strait hazard pay but that had limited success at best. Ultimately, an empress came up with the idea of giving convicted criminals pardons if they swear to defend the Demon Strait made up for their recruitment/retention issues. Convicted criminals have to way a certainty of execution against the possibility of their soul being destroyed. Some time ago, the Deep Waters Legion once had to deal with incursions from barbarian tribes in addition to Void demons, but those times are long gone. Most of the northern tribes now know better than to mess with the Oshamni Empire. In fact, some of the northern tribes are now tentative allies to the Deep Wardens Legion. The legion will sometimes trade equipment to the barbarians in exchange for food or information.