Background

Attempts at peace through communication was doomed from the start, as the alien creatures showed through their wanton destruction of colonies that they had no interest in co-existence; only war. And so it has been for the past five decades that the verdant world of Cadeca has served as a battlefield of legendary proportions, with each side absolutely unwilling to back down. 

These creatures are - for lack of a better term - known as dragons, due to their resemblance to the mythological creatures. As well as being highly aggressive, they are biologically capable of space flight, able to breathe hull cutting plasma beams, are highly agile and immune to most conventional weaponry, including nuclear warheads, due to their incredibly tough skin.

Compared to humans, dragons are few in number and are solitary creatures, although a few have been known to speak to each other and co-operate to take down colonies, space ships, etc. For the most part however, they are more likely to be encountered individually, as one is all it takes to wreak absolute havoc, and they seem to be aware of this.

So far, the dragons haven't spread anywhere beyond Cadeca. They seem content to hold their control over most of this one planet, but they occasionally make forays against the colonies or the ships in orbit. These attacks are most likely retaliatory, but there's no doubting the intensity of their aggression. If given a chance, they would burn every colony and chase the survivors out of the system, so there is no choice but to hunt them down in return. A good offense is the best defense.

The appearance and size of dragons vary greatly, the smallest being as large as an elephant and the biggest being comparable to the Hindenburg. Either way, they are hostile, cunning and deadly, and the only way to combat them is either with overwhelming firepower or the especially daring bravery of soldiers specifically trained for the task.

These soldiers are known as Raiders, to reflect their nature as surgical strike teams that are meant to find the enemy, kill as many as they can in as little time as possible - two or three dragons being a good number in a single sortie - and then return to base immediately for rearmament. Casualty rates are high, so veterans are relied on to ensure that humanity acquits itself well in combat.

Each Raider is equipped with Slayer Gear which consists of power armour that magnifies it's wearer's strength, allows for leaping over great distances and heights (which can be further boosted with jet propulsion) and provides an energy source for the specialized shield and weapon system.

The shield, which can be physically held or attached to the Raider's offhand, contains the same technology space ships use to protect against high energy projectiles, such as a dragon's plasma breath, so a Raider is able to meet the enemy's attack head on, albeit for a short time. The shield can also be used offensively by unleashing a massive amount of kinetic force, enough to bash a dragon and stagger it or knock it out of the sky, though this costs a heavy amount of energy from the armour's already limited power supply, which can either last a month or a day, depending on usage.

The primary weapon of a Raider is the Gladius pattern 'Buster' gun, which can fire low power bolts of plasma or a single devastating round, meant for delivering the coup de grace after using the gun's super-steel bayonet to breach the skin over a dragon's heart, the only vulnerable point in their natural armour due to its prominent seam. Although a dragon's sternum is considerably hard, more so than the material of the Buster gun's bayonet, it lacks the same properties that renders the skin immune to heat and radiation, and therefore can be pierced with sufficiently powerful plasma weaponry. Another vulnerability to exploit is a dragon's eyes, though they are often the riskier target.

Characters

Your character is a Raider. He or she can come from anywhere, whether it's one of the colonies on the planet Cadeca, or be raised on some civilian or military vessel, maybe even Star Fort Praetorius, either way, your character is going to be a dragon slaying badass... or plasma fodder.

Now here's a few things about the colonies on Cadeca. There used to be about thirty or so, each one being self-sustainable with a population of a few thousand inhabitants. They're still self-sustainable, except now there's just twelve colonies left, and they're only still around because they're directly underneath Star Fort Prateorius. 

Despite this protection along with heavily fortified walls, colonists live in constant fear of the dragons that could swoop in at any time to wipe them out. Even so, many would never dare to leave, because dragons have been known to intercept space shuttles, blow them up and then flee before any retaliation can be mustered.

A rare few colonists are determined or crazy enough to go to Star Fort Praetorius to apply for becoming a Raider, and even fewer are able to pass the training, in which deaths are not unheard of. In any case, enough time has passed for Raiders to get some equipment onto the ground and rearm in the colonies, instead of having to go all the way back to Fort Prateorius the way they used to. It's always a big deal when a group of Raiders goes out or comes back from a sortie, and whether they're considered heroes or fools of the highest order, they are more or less the only ones taking the fight directly to the dragons.

Those raised in the Fort are almost guaranteed to become Raiders as the previous generation's purpose was to win the war for Cadeca. That war is still being fought and the older generation is few and, well, old, so the young must eventually take their place. Bristling with powerful guns and guarded by a fleet of battleships, Star Fort Praetorius is nigh impregnable, though it has nearly faced destruction before from a massive dragon attack, which was led by the largest among their kind on record. The Fort and its inhabitants still bear some scars of that incredible battle and that big dragon is still lurking about somewhere.

Those from anywhere else only know what they've been told by the media or whoever roped them into it. Recruiters have been known to go to places as far away as Earth to seek potential Raiders and there's glory to be had in slaying dragons... if only they knew the truth.