Not Started Border Crossing


Join Date
Nov 12, 2018
Campfire here

Four and a half years ago, invaders from another dimension, called ‘Neighbours’, invaded the city of Mikado in Japan. However, a mysterious agency called ‘Border’ appeared, and repelled the attack, saving the city, though leaving it in ruins, and not without casualty. From then on, the Neighbours began frequently attacking Mikado, though in much smaller scale. Border, however, was always there to repel the attackers, and became an officially sanctioned Defence Force for the public, which also allowed anyone found to be capable of becoming a Border agent to freely join if they chose.

Over the years, Border has grown, now having four additional branches stationed in Mikado. However, just as Border’s size and the quality of their agents have grown, so too has the danger posed by those who would call themselves ‘Neighbours’. In recent times, the automated Trion soldiers that act as the main fighting force for Neighbours have been found to appear in areas of Japan other than Mikado, and now there are even reports of some appearing in the Americas, Africa, and Europe.

The boy cowered under the sight of the grey, arthropod-esque creature that had cornered him. Everyone else had managed to run when it and those other huge white monsters had appeared out of the portal, but he’d tripped, and he had nowhere to go. It raised one of its claws, and he closed his eyes in fear-

And then opened them, to see it dead on the ground before him, leaking some sort of green mist in the air from where it had been slashed through lengthwise. In between him and it was a teenager, not that much older than him, wearing a simple blue jacket and black trousers, holding what seemed to be a sword made out of light.

“Yo!” His saviour began, before then continuing to speak. However, the boy understood none of the words coming out of his mouth, and the teen seemed to realise this, muttering something, before tapping his ear and saying, “Translator, on.”

“Yo again! Sorry about that, I’m still not used to operating in this country. Looks like I got here in time, though!” He said, before spinning on his heel and throwing his sword into the mouth of another one of the scorpion things, killing it instantly. “You’re safe now. You’ve got the power elite, Yuichi Jin, here to save the day.” The sword he had thrown seemed to fade from existence while an identical one appeared in his hand. “But I’ve got other places to be. You’ll be fine, though. My Side Effect tells me so.”

He then jumped on top of a building that had been ruined by the appearance of the monsters, before jumping from that and away to some other location. But just before he left, the boy he had saved caught a glimpse of the logo on the sleeve of his jacket. Border..?

The Border Defence Agency managed to catch wind of a coming large-scale invasion in Cardiff, similar to the one that had occurred in Mikado. Multiple B-Rank units and A-Rank agents were mobilized with immediate effect, including the likes of Chano Unit, Nasu Unit, Ninomiya Unit, Jin Yuichi, Midorikawa Shun, and Miwa Shuji, with Fujin, to name a few. Along with them went Kawasara Katsumi, Kinuta Motokichi, and Shinoda Masafumi to deal with the local government in the creation of a new, permanent base overseas.

The U.K. Government quickly agreed to this after seeing first hand what kind of devastation the Neighbours were able to cause even with Border’s assistance, and Border’s first foreign branch, the Cardiff Branch, was formed.

Just like the original Border H.Q., word quickly spread, and applicants flooded in to become agents, to be heroes like the ones that had saved them before. Some did it because their heroics had inspired them. Some did it to get revenge on the Neighbours for taking away their loved ones. And others still simply thought it would be fun. Whatever their reasons, Border would take them all – if they had the talent.

✜ All Marriland rules and RP rules apply.

✜ There are no length requirements to the forms, so if it’s amazing and short you can get in just as if it’s a book but **** you won’t.

✜ Apps must be posted in the Campfire. PM me if u have questions

✜ You are allowed to try again as many times as you want if the form is pending. If the form is denied, you cannot remake a form for that character, but you can make a different one if you choose to. If your forms are denied twice in a row, or three times in total, you'll be barred from creating any more characters, though any characters that have been accepted will remain a part of the RP.

✜ Forms will be accepted on a first come first serve basis. I’ll be starting up once we have two or three forms, not including my own, which will form a B-Rank squad. However, don’t be discouraged, as applications will never close. You can join in once the RP begins, or make another character if you so wish.

✜ In addition to the above, the formation, dissolution, joining or leaving of any squads formed in the RP is entirely up to the members of said squad. If, for example, your character is in the initial squad that’ll be created with the start of the RP, but a second squad is formed that they would prefer to be in, if that squad’s captain is fine with having them, they can leave whenever they choose. A character can also leave their squad to perform solo if they wish, though I wouldn’t advise that unless they’re already A-Rank, since they can’t rank up from B by themselves.

✜ A squad can anywhere from 2 to 4 combatants, as well as an Operator. Operators will all be NPCs, as I imagine most people would find that role rather boring.

✜ Squad captains will also need to find/design a uniform and logo for their squads. This will be what all members of the squad wear while in their Trion bodies. If you can’t think of any, look at the uniform designs of squads in the actual series for some ideas.

✜ I reserve the right to accept/deny for any reason I see fit.

✜ Posting once a week sounds doable. I’m probably gonna be somewhat lax with that, but still let’s try to keep this semi-active.

✜ While I advise starting your character off at B-Rank, you can start at C-Rank or A-Rank if you want to. Don’t make an S-Rank character without asking me first.

✜ While you can give your character a Side Effect, it’s not necessary. If a form is good but the Side Effect is too powerful, you’ll be accepted, but either you’ll need to tone it down or remove it entirely.

✜ The Trigger Set that you’re putting in your form is not permanent – you can change it at any time once you have been accepted, it’s simply so we can keep a record of what Triggers your character is currently using. In addition to this, you can use modified Triggers if you want – just tell me beforehand and I’ll decide if the modification is valid or not.

Read all of the posts under this one before making your form. I mean that. Unless you’ve watched or read the series, in which case you probably know what most of this means.

Name: self explanatory

Gender: same as above

Age: The age range of Border agents is quite large, with the youngest so far being 13 and the oldest being 25. However, for the most part agents are anywhere from 15 to 20, so try to hit anywhere in that range.

Classification: Are they an Attacker, Gunner, Shooter, Sniper or All-Rounder?

Rank: no S-Ranks pls

Appearance: Picture, description, or both. Make this of the character in their regular body.

Personality: self explanatory

Brief Bio: I want to know how your character found out about Border, what happened to them in the Large-Scale Invasion, why they joined and how long they’ve been a part of Border. Still doesn’t need to be super long tho

Side Effect: Either N/A or whatever you dream up. Just remember to not make it too strong.

Trigger Set: Up to eight triggers. Two Shields and a single Bagworm are recommended no matter what, and Bagworm is essentially necessary for Snipers or anyone with a Sniper Trigger. For Gunners/All-Rounders, to specify what Gun Trigger they use, simply put the bullet type followed by the gun, for example Asteroid (Assault Rifle), or Meteor (Grenade Launcher). If there is no firearm specified, I’ll assume it’s a Shooter Trigger.

Other/Text Colour: put ur text colour plus anything else here
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Join Date
Nov 12, 2018
Important Information
As you may have been able to tell, this RP is not original. It is based on the anime/manga called World Trigger, and so obviously knowledge of the series may help your enjoyment and understanding. However, this RP will run parallel to it – in the sense that while certain pieces of knowledge from the series are essential to know to understand the world, others are not. To put it into simpler terms, the plot of the actual series is largely irrelevant to this, although even if it weren’t, the manga has been on hiatus for over two years now anyway, so there would only be a small overlap.
However, characters from the main series probably will show up as NPCs, and the essential details about the world, Neighbours and Border will of course be the same between the two, most of which I will cover in this post. For that reason, this is pretty essential to read, but you could theoretically skip it and get by.

ok so I found this out right when finishing up but actually the manga is finally off of hiatus after 2 years!! this was completely unexpected by the way so if new **** is revealed in it that's cool or relevant to this it will be retroactively added ok cool bye going to read some world trigger

Trion is this world’s magical energy source. Think along the lines of chakra from Naruto, ki from Dragon Ball, that sort of thing. However, unlike most of these energies, Trion is much more pseudo-scientific. Trion itself does not grant people any special magical abilities, except in some special cases. These ‘special cases’ are referred to as Side Effects, and only occur in people with very high natural Trion levels. What your Side Effect is can vary wildly from person to person. Some examples we have seen have been lie detection, limited precognition, and the ability to sense when Neighbours are coming, and incredible hearing. However, while you could call each Side Effect a super power, none has ever been shown to be on the level of say, a Quirk from My Hero Academia. They are all very specific and limited in scope, and people without Side Effects have been shown multiple times to be just as capable as those with them.

Continuing on, having a Side Effect is also not a requirement to becoming a Border agent. While plenty of them do have them, just as many, or even probably more, do not.

Aside from that, Trion again has no effects in and of itself – it’s simply created by a special organ and then shuttled around the body, similar to the cardiovascular system. However, Trion can be used to power special devices called Triggers. These are what Border agents use to fight.

A Trigger is a product of Neighbour technology that manipulates and is powered by trion. Despite being often used for combat purposes, Trigger technology also has other functions, and in fact it is regarded as the cornerstone of the entire Neighbour civilization. Combat-oriented Triggers have massive firepower, and are the only weapons capable of damaging and even destroying trion bodies and trion soldiers.

The Triggers developed by Border, and indeed, most Triggers, switch out the user’s ‘flesh and blood’ body with one formed out of Trion. This gives the user much enhanced physical capabilities, making even the weakest Trigger users capable of scaling small buildings in a single leap, and moving large amounts of rubble, as well as protecting the users actual body from harm in a fight. As an added precaution, Border’s Triggers are equipped with a ‘bail out’ function, where if the user’s Trion body is ever destroyed, their real body will automatically be returned back to base. Agents can also bail out with a verbal command.

A Trion body can be destroyed in two ways – if the Trion Supply System is damaged or destroyed, or too much Trion is lost through wounds and damage. While this sounds complicated, in essence it just means that they’re vulnerable to the exact same things as a regular body would be, but simply can’t be damaged through non-Trion means.

A Border Trigger Holder is also capable of holding 8 different Triggers within it, though C-Rank Trigger Holders can only hold one Trigger. A universal rule of Triggers however is that no matter how many an agent might technically have access to, they can only ever actually use two at a time, even if they theoretically had the Trion to activate all of them simultaneously.

Border Agents
There are four classifications of Border agents – C-Rank, B-Rank, A-Rank, and S-Rank. C-Rank agents are trainees, B-Ranks are the main fighting force, A-Ranks are the elites, and S-Ranks are an entirely different classification separate from the other three, and cannot be entered into or left by normal means. An agent can be promoted through the ranks from C to A, as well as be demoted from A to B, but an agent is only ever S-Rank if they have a Black Trigger in their possession. A Black Trigger is a special, extremely powerful type of Trigger that is unique, and can only be used by certain people, who those people are being determined by the trigger itself. A Black Trigger can only be created by someone sacrificing their life force to make it.

Within A and B-Rank, there exist further classifications of the units. Border’s offensive Trigger technology is split into four main categories – Attacker Triggers, Gunner Triggers, Shooter Triggers, and Sniper Triggers, and so agents are also split into these categories depending on what their Trigger/s of choice are. In addition, there also exists a fifth classification, and depending on who you ask, a sixth – an All-Rounder. An agent classified as an All-Rounder is one who has reached at least 6000 points with both an Attacker and a Gunner or Shooter Trigger. The debated sixth classification is known as a Perfect All-Rounder – an agent who has reached 6000 points with an Attacker, Gunner or Shooter, and Sniper Trigger.

C-Rank and S-Rank agents aren’t classified this way – C-Ranks are not because they are still counted as trainees, while S-Ranks don’t fit into the specific bubbles due to the uniqueness of Black Triggers. Also, an agent is not locked to Triggers of the specification they are assigned as on paper. For example, Arafune Tetsuji is technically classified as a Sniper, however was originally an Attacker, and still uses his Attacker Trigger of choice, Kogetsu, along with his Sniper Triggers. As you can also see from the above example, agents can also choose to change their classification whenever they wish, as long as they have enough points in the corresponding Triggers to qualify.

When a new agent joins Border as a trainee, they begin as a C-Rank with 1000 points. Depending on how well they perform on their entry tests, they will be given extra points, and then can gain further points through either completing training sessions, or through solo Rank Wars, which are battles that two agents can organise to have with each other, with the winner gaining points and the loser of course losing them, the amount of which is determined by the difference in their points before the battle began. Once an agent reaches 4000 points, they are automatically promoted to B-Rank, and then classified as an Attacker, Shooter, Gunner or Sniper depending on their Trigger of choice. Sniper trainees can also be promoted if they manage to make the top 15% for three weeks in a row.

An agent's points correspond to their highest score with any one Trigger in their possession. Dropping below 4000 points with all of one's Triggers does not result in the demotion from official agent to trainee, which is however the case if the score of any one of the agent's Triggers drops below 1500, but this has never occurred thus far. An agent who reaches 8000 points with any one Trigger is said to have reached 'master class' with it. Official agents adding a new Trigger to their set will start from 3000 points (4000 if they are master class). In Rank Battles, if an agent fights with two Triggers, the one which dealt the final blow receives 70% of the total score, the other one 30%.

Once an agent is B-Rank, they can have Rank Wars with other B-Rank and A-Rank agents and will start being ranked by their points in their classification. However, no matter how many points they gain, an agent cannot become A-Rank by themselves, even if they were theoretically the No. 1 Attacker and No. 1 Agent by points. To become A-Rank, a B-Rank agent has to instead form or join a B-Rank unit and then participate in Unit Rank Wars, and then become the 1st or 2nd ranked B-Rank unit. Then, they can have a special Unit Rank War, and if successful, the unit and all the agents within it are promoted to A-Rank. However, if a B-Rank agent is good enough, an already existing A-Rank squad may ask them to join their squad, in which case the B-Rank will be promoted to A-Rank automatically upon joining.
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Join Date
Nov 12, 2018
Triggers (cont.)
Although Triggers are made to be standardized and mass-produced, once an agent reaches B-Rank they gain the right to somewhat modify their Triggers, like for example adding a guard onto Kogetsu. Once an agent is A-Rank, they can modify them even further, to the point where some might even consider the modified Trigger separate from the original, like for example modifying Kogetsu, which is normally shaped like a katana, into a spear. A-Rank agents are also allowed to use Triggers that are still prototypes.

Attacker Triggers
There are three Attacker Triggers – Kogetsu, Scorpion, and Raygust. Kogetsu was the first to be developed, and is the simplest, being a katana with a Trion blade. It has the highest attack power of the three and the second highest durability, and has two Optional Trigger attachments – Senku, which allows the user to extend the blade for a short period, and Gen’yo, which allows the user to change its shape. It is Border’s most popular Trigger.

Scorpion has the lowest durability of the three Triggers, and the second highest attack power. While it normally takes the form of a short sword made entirely of light, its shape can be freely changed, and it can appear from anywhere on the users body, including strange spots like their back, knees, or their forehead. While it has no Optional Triggers, it does have many special moves that only it can use. The first is Mole Claw, which is creating a Scorpion blade that goes into a wall or floor and then curves out of it to surprise the opponent. The second is Branching Blade, where the user splits the Scorpion inside their body to then cause one Scorpion to seemingly have two blades. Finally, there is Mantis, which can only be used if the user's Trigger loadout contains two Scorpions. Mantis is a lethal, whip-like attack with longer range than Kogetsu that works by the user whipping their hand towards the opponent and forming a Scorpion as long and thin as possible, and then on the end of that Scorpion forming a second Scorpion to act as the blade. Mantis is incredibly powerful, but requires an intense amount of precision, experience and concentration to use, to the point where that even in the master class of Attackers, only two have been shown to use it successfully in combat, and only one uses it consistently.

Raygust has the highest durability of the three Attacker Triggers by far, but also the lowest attack power – if the other two are swords, Raygust is closer to a bat. However, like Scorpion, its shape is capable of changing, but it must always be attached to its handle. For this reason, commonly its shape is only changed to that of a large shield to take advantage of its durability. It has a singular Optional Trigger – Thruster, which when activated launches Raygust forward with enough force to allow it and the user to fly for a short distance.

Gunner and Shooter Triggers
Although Gunner and Shooter Triggers are separate, they are both subsets of the other, as their offensive Triggers are technically identical and the difference between them is simply how those Triggers are utilized.

Both Gunners and Shooters use the four projectile Triggers – Asteroid, Meteor, Viper and Hound. Like all Triggers, the power of all of these is highly dependent on the Trion levels of the user, but Gunner and especially Shooter Triggers see the effects of this the most. However, Shooters use them by forming cubes of Trion and firing them from those, while Gunners have guns created from Trion and use them as a medium to fire the Triggers. Gunners have five additional options in terms of what type of gun they use – those being pistols, grenade launchers, assault rifles, shotguns, and miniguns, with assault rifles being the most popular for pure Gunners, and All-Rounders preferring pistols.

Asteroid is the basic projectile Trigger, essentially being a regular bullet in Trion form. It has the highest bullet speed, power and range, but lacks any of the other special abilities the other projectiles have. Meteor is the slowest bullet, and lacks the penetrative power of Asteroid, but it explodes on contact and so can deal damage on a large scale. It’s also unique in that when used by a Gunner, only a single shot can be fired at a time, but Shooters can split the Trion cube they formed it with to fire multiple, like they can with any other Trigger. Viper is fast, but has the second-worst range. When fired, it follows a set trajectory programmed in by the user, although it is extremely difficult to do this in the middle of combat, so most agents simply learn a few useful trajectories and preprogram them. In Border’s history, there has only ever been two agents who are capable of controlling Viper mid-combat, making their versatility almost unparalleled. Finally, Hound is the second slowest, but has the second best range and power, and is a homing bullet, capable of tracking foes by curving. It can either be guided via Trion detection or through the users eyesight.

The projectile Triggers also have the unique property of being able to be combined to create special bullets with the properties of both of the ones that were combined. For example, Meteor and Viper can be combined to create Tomahawk, which is a composite bullet that’s trajectory can be controlled and explodes on contact, but is extremely hard to control properly and moves slower and has less range than Viper.

Shooter and Gunner Triggers have one Optional Trigger attachment that they all share - Starmaker, which places a marker on a Trion body after a bullet with it active comes into contact with one. Once the marker is placed, the Trion body will remain detectable no matter if they use a Trigger that would hide them from the radar, or one that would turn them invisible.

Sniper Triggers
Similar to Attacker Triggers, there are three Sniper Triggers – Eaglet, Lightning, and Ibis. Eaglet has the longest range, Ibis the most power, and Lightning the highest bullet speed and refire rate. As they’re all still just snipers at the end of the day, they’re not as interesting to talk about as the other offensive Triggers. In general however, Sniper Triggers are very powerful, capable of destroying Trion bodies in one shot provided they get a clean hit.

They have no Optional Triggers specific to them.

Optional Triggers
Aside from the few mentioned earlier, there are also a few Optional Triggers that don’t require another, main Trigger for them to function, namely Shield, Bagworm, Grasshopper, Chameleon, Spider, Escudo, Idaten and Teleporter. In addition, there is also the Optional Trigger Lead Bullet, which does need a main Trigger to function, but this main Trigger can be a Gunner, Shooter, or Sniper Trigger.

Shield is rather self-explanatory, simply raising a shield that blocks attacks. The size of the shield can be freely changed without expending Trion, however this means that larger shields have their Trion more spread out and are therefore weaker than a smaller shield made by the same person. In the same vein, a super tight, compact shield can be very powerful, and can potentially block even sniper fire from Eaglet and Lightning. There is also a secondary mode of Shield called Affixed Mode, where the user can cause their Shield to surround themselves and remain stationary in return for increasing its strength. However, this is rarely used, as Trigger battles tend to be incredibly fast and mobile. Shield can also be activated and put on a teammates body to protect them if necessary, as well as two Shield Triggers can be activated at once to achieve what is known as Full Guard - an even more powerful defensive state. While not technically required, most agents place two Shields in their Trigger loadout, and every agent has at least one, the only two to only use one having another defensive option in their loadouts.

Lead Bullet is rather simple as well, simply making it so that the bullets fired by any of the three types of long range Triggers no longer do any damage, but instead convert the part of the Trion body they hit into weights. Because they no longer do any damage, they are also no longer blocked by Shield, and simply passes through.

Bagworm takes the form of a sniper’s cloak surrounding the user, and makes it so they no longer show up on the radar, though they are of course still visible to the naked eye. If the user has been hit by Starmaker, Bagworm has no effect. Similarly to Shield, most agents automatically put Bagworm into their Trigger Holders as it is incredibly useful, though again it's not required. Snipers wear Bagworm at all times during combat to make it harder for the enemy to find them and take them out at close range.

Chameleon turns the user invisible. However, while Chameleon is active, they are incapable of using any other Triggers – the moment one is activated, Chameleon automatically deactivates. In addition, they still show up on the radar even when it is active. If the user has been hit by Starmaker, Chameleon has no effect.

Grasshopper allows the user to place ‘platforms’ that propel whoever touches them forward. Crucially, the Trigger is not the platforms themselves, but rather what is used to place them, so more than two can be laid at a time, and once they are laid, the user is free to use whatever other Triggers they like.

Similar to Grasshopper, Spider allows the user to place wires around the battlefield. Like Grasshopper, the wires are not the Trigger, the thing placing them is. The wires can be made any colour the user wishes, and can be used to impede mobility or in combination with Meteor to make tripmines and other traps.

Escudo is another Trigger that places something to effect the physical world - in this case, a large, shield-like wall that can take a lot of punishment. Just like Spider and Grasshopper, the walls that it places aren't considered Triggers themselves, and so many of them can be placed at a time. Escudo's walls can take much more damage than Shield can, however once placed the walls are immobile, and unlike Shield they are also opaque, so they cut off the user's line of sight. Because of this, and due to the fact that creating even a single wall requires a large amount of Trion, the Trigger is considered old and not that useful by modern standards.

Teleporter is rather self-explanatory – it allows the user to teleport a few metres in the direction they’re facing, and then has to cool down. The longer the distance travelled, the longer the cooldown. It is a prototype Trigger.

Idaten is similar to Viper in that it moves something along a set trajectory at extreme speed, but in this case it is the users body. While it technically doesn’t require the use of any other Trigger, it is normally used in conjunction with an Attacker Trigger to slash the enemy as the user moves past them. It is a prototype Trigger.

In addition to all of these, there is also the Bail Out Trigger mentioned before, and the Radar Trigger, which brings up a Trion radar of the surrounding area. Both of these come standard with every Border Trigger Holder except for those given to C-Ranks, and are not counted towards the 8 Triggers each Holder can carry.
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Join Date
Nov 12, 2018

Before it became publicly known, Border was a secret organization with the purpose of being an intermediary between ‘Earth’ and Neighbours. About four and a half years before the start of the series, Border made its first public appearance when the First Large-Scale Invasion occurred. Soon after that, Border built their Headquarters in the middle of an area known as the Danger Zone and began recruiting new members.

The management supervises all Border employees and the safety of Mikado City from Neighbour-related threats. They are also involved in tasks such as P.R., gathering of funds, and supervision of the R&D Department, as well as in the organization of away expeditions. Engineers are in charge of everything all matters technology, while Operators provide intelligence to agents and serve as their connection to HQ. Agents fight Trion Soldiers and similar threats. However, they are not always at the scene in time, leaving citizens to fend for themselves or if there's an agent, to fight it themselves. Some agents are also involved in P.R. initiatives and recruiting. A-class and B-class members are paid, but C-class trainees are not, as they are not official agents and are not supposed to engage in combat outside of training. However, they have recently received clearance to activate their Triggers to help with evacuation and rescue during emergencies.

The core of Border's operations is a massive fortress with trion cannons and reinforced walls. Aside from offices, common areas and other ordinary spaces, it contains laboratories for the engineers, control rooms for Operators, private rooms for official units, and virtual spaces for agents to train in. Deep underground is also a vessel made out of trion to travel to the Neighbourhood. Around the headquarters is an unhinabited, devastated portion of Mikado City where Gates are redirected, so they open away from ordinary citizens. However, this technology cannot prevent Rads from opening portals elsewhere.

The Cardiff Branch of Border, while not as large as the original H.Q. and not possessing its own vehicle for travelling into the Neighbourhood, has a similar set up, built in an area not reconstructed after the Cardiff Large-Scale Invasion. This is partially due to the current lack of engineers, as the current recruits coming in tend to simply quit Border if they are not made into an agent directly involved with combat.

Neighbours and the Neighbourhood

A Neighbour is an interdimensional and extra-terrestrial race of humans and humanoids that live within the Neighbourhood, living within separate planets opposite to Earth. While most neighbouring planets have inhabitants that appear like regular human beings, others have inhabitants that are humanoid in appearance, but have different physical traits that distinguishes them and make them overall less human, if not completely inhuman. This along with the fact that they are from separate worlds makes them a completely unique species altogether. They were accused of attacking Mikado City four and a half years ago, thus causing stigma towards them which has only grown with the recent Cardiff invasion.

The Neighbourhood, also referred to as the Neighbour World, is the world from another dimension where Neighbours and Trion Soldiers originated.
Each country travels across the sea of darkness on their own orbits, like average celestial bodies. For this reason, another name for the countries in the Neighbourhood are ‘planet nations’. Their movements are a bit different from those of planets orbiting the sun, but many of planet nations brush by the human world while revolving closer and farther. Every planet runs on a star (which itself is a Trigger). The star must be kept fuelled, or it will die, and the nation would eventually crumble. This is why when certain countries invade Earth when they approach it – the reason for the invasions is to capture humans with high Trion levels and use them to power failing stars, which are also known as Mother Triggers. Earth specifically is normally chosen because until recently, its knowledge of Trion, Triggers, and the Neighbourhood was extremely lacking and primitive, making it an easy target. In modern times though, even large, powerful nations have to send their strongest Trion soldiers and elite Trigger users – in some cases even Black Trigger users – to obtain anything meaningful, due to Border’s defensive work.

Certain planet nations don't have fixed orbits and fly around freely in the Neighborhood. These have been called ‘errant nations’.