Lukas Keath

Lukas Keath is the Primarch of the Tenth Legion - the Obsidian Guard -, and Lord of the Feuerreich. As a result of his reforms, his Legion grew to be the second-largest and earned a proportionately massive roll of honour unmatched by any other. Possessed of a fiery temperament he is the most brazen and passionate of the Emperor's sons, bellicose in all respects. This facet of his personality was kept in check by another, his immense self-discipline. Unquestioningly loyal he fought diligently during the Great Crusade to turn the His dream into reality and desperately during the Five Ruins to prevent it from falling apart.

Origins
The boy who would one day become known as Lukas Keath began life as his brothers did in the Emperor's gene labs beneath the Himalazian Mountains but was sent hurtling through Space by unknown means. He landed upon the world of Feuerstadt, in the Northeast of what would become Segmentum Solar but that at the time being was an isolated, volcanic death world. Shortly after crashing in the ash plains outside the city-state of Sturmhafen Lukas was brought before the Council of Oligarchs who would decide his fate. Some called for the strange child to be executed as a mutant abomination but coolers heads prevailed and it was decided he would be taken into the household of one of the Oligarchs, Wolfrich Keath.

Lukas was raised as an adopted son to Wolfrich, taught military strategy, swordcraft, blacksmithing, engineering, oratory, philosophy, mathematics, and all other subjects deemed important for a member of the nobility. However, that final word rang sour in Lukas's ear, who believed that his life was just as worthy as the cobbler who wasted away from noon to dusk to feed his children or the common rifleman despite his indisputable superiority who protected the city from its enemies. As Lukas grew he railed against the Oligarchs for getting fat and rich while the people were barely getting by. The enmity accrued for his words grew too until an attempt was made on his life while he was asleep in his home. A massive explosion demolished the Keath manor, Lukas managed to escape but Wolfrich was killed in the ensuing collapse of the building. Lukas, instead of seeking medical attention slipped into the shadows of the city's underbelly to fool his enemies into believing their assassination succeeded. He gathered a small army to his cause and turned them into a lethally effective fighting force, using this Obsidian Guard, so named for the volcanic glass so common near the magma chamber of the dormant volcano Sturmhafen built inside, Lukas deposed the Oligarchs. Few in the military raised a hand against the Guard, indeed some even joined them in their march on the halls of government. What followed could not even be described as a battle, massacre is more like. The Oligarchs' guards whether out of true loyalty or simply a desire to retain the privileges their patrons granted them tried in vain to stop Lukas and his army but failed utterly. In a day, Lukas became the sole ruler of Sturmhafen and set about reforming the structure of the government to better serve the people while also preparing for war. Other city-states needed liberation and Feuerstadt itself needed to be unified, so Lukas led a grand crusade, conquering the whole of the planet within a year as each city brought under control contributed resources, supplies, and troops. After the last enemy citadel, Feuerlandung, fell, the Emperor of Mankind arrived to bring Lukas home to Terra.

After spending several years on the Throneworld learning from the Emperor, his elder brother Alexandros, and the Captain-General Constantin Valdor Lukas set out to put his schooling to use leading his legion in the Great Crusade.

Early Career
The first test of Lukas's progress was the campaign that would come to be known as the Feuerreich Crusade, named such for the sub empire it created. At the conclusion of the Crusade, the Emperor and Lukas parted ways, the former confidant in the latter's abilities enough to leave him to his own devices. Determined not to fail his father Lukas devoted himself to doing all in his power to make the dream of the Great Crusade a reality. When Lukas was first reunited with the Tenth Legion before the Feuerreich Crusade he made little changes to their doctrine or organization, desiring to see them in action before making sweeping alterations. Although performing admirably by any standards Lukas knew his sons could do better, if only put in the right place and shown how to do so. Lukas discarded the structure laid out in the Principia Bellicosa for the more flexible Corps system, which increased the Obsidian Guard's ability to respond quickly and with appropriate force to any threat. He also sought to ensure the smooth integration of Feuerstadt- and Terran-born Legionnaires, melding the two cultures into one. Once the process was complete Lukas departed his home to bring the light of the Imperial Truth into the darkness of the void at the head of the newly christened Obsidian Guard.

Throughout the following decades, Lukas built up a reputation, though it is a matter of debate whether it was deliberately cultivated or a natural consequence of his actions. In either case, Lukas became renowned for his expertise at siege warfare, felling fortresses that had delayed other forces, even other legions, for months or years in mere weeks. But his skills did not stop at the destruction of buildings, he was equally adept at the raising of them. Before Lukas and the Obsidian Guard moved on they erected grand structures to act as reminders of Imperial rule. It was from these bastions that the Obsidian Guard would repel the onslaught of the Ruins.

Rivalry with Mars
What started as a mere distrust between Lukas and the Martian Tech-Priests in the very late 800s of M30 had grown into a bitter hatred by the 950s. Lukas saw the Cult Mechanicum as an existential threat to the Imperium's future and in turn, Lukas was viewed as one of the few in the Imperium with the power and motivation to strip the Mechanicum of religious freedom granted to them by the Emperor. Even before the Emperor's disappearance, Lukas began experiments on Xenos technology, seeking ways to better combat the alien menace by whatever means he saw fit. This brought about numerous arguments between Lukas and his father that persuaded the Primarch to take missions ever more distant from Terra. Unhindered by any oversight Lukas continued his work, taking a particular interest in the psycho-reactive armor of the Eldar and trying to improve power armor with it. His efforts were halted when the Emperor vanished, as Lukas grieved for his father and raged at himself for spending their last interactions arguing. After the Conclave of Terra, however, he resumed them, which eventually earned him the ire of the Regent and a censure. Following this development Lukas switched his focus, abandoning the idea of eradicating the Cult Mechanicum in favor of simply curtailing the power of Mars. To that end, he allied himself with those Forge Worlds already opposed to the Red Planet, whether out of doctrinal disputes, political infighting, or for any other reason. Lukas did not care why they hated Mars, only that they did and were willing to work with him.

Personality
Lukas is gregarious, humble, honorable, loyal to a fault, and passionate but also stubborn, hot-tempered, and even merciless at times. Sometimes it feels as if he becomes a different person, flipping a switch and changing demeanors as one would change outfits. But this is an oversimplification, Lukas has all the qualities previously mentioned at all times, which come to the fore vary based on the situation he finds himself in.

Wargear

 * Armor Indomitus - Wrought by Lukas's own hands this heavily modified suit of Cataphractii-Pattern Tactical Dreadnought Armor is nearly unrecognizable from its original form save the superficial appearance. Over the course of months, the Primarch systematically tore out every internal component and replaced them with improved variants of his own design.
 * Tyrantsbane - When Lukas was given command over his legion following the Feuerreich Crusade the Emperor gifted him the mighty Force Hammer Tyrantsbane, a gargantuan weapon as tall and heavy as an unarmored Space Marine. In the hands of Lukas and empowered by his psychic abilities Tyrantsbane has enough power to send enemy tanks flying through the air as if they weighed nothing or pulverize whole squads of enemy foot soldiers.
 * Whispered Truth - If the need ever arises for more firepower Lukas will turn to another of his creations, Whispered Truth, a twin-linked Volkite Caliver of peerless quality.