Ionnacaira

Ionnacaira is

Background
Ionnacaira, the world upon which the Storm Angels have chosen to settle in 758.M41 is classified as a Feral Ocean World by the Adeptus Administratum. 80% of its surface is comprised of water, the 20% remaining being the millions of islands, none larger than 1128 km² (436 sq miles). Most of those islands are comprised in the large tropical zone of this world, only a few archipelagos doting the Northern and Southern hemispheres. Because of this, the population of those two zones are extremely isolated and the Storm Angels have chosen to not make use of them as potential recruit, instead focusing on the tribes populating the millions of jungle islands of this world.

Those populations appears to be descendants, or to have evolved to look like, of the indigenous populations of the ancient South Merica of Terra. In fact, the name of the planet itself, Ionnacaira, is purported to be from the long lost Island Aa'wa or Ara'ak, an almost dead language by the end of M2, which signifies "Island/World of Iguana". Any visitor would find the name well earned, since iguana-like reptiles can be found on every islands, even the coldest ones in the Northern and Southern oceans. However, the natives did not name their planet from those inoffensive creatures, instead using periphrases to not speak the name of the greatest predators of this planet, know by the Imperium as the Sea Abomination, and as the Iawanaria, the Serpent, by the natives.

Those creatures, which can reach up to 25 meters long (82 feet) and are large enough to swallow a man whole, and their bodies are able to slither extremely fast on the ground, once they emerge from the sea. Most atrocious perhaps is the fact that thousands of small appendages allows it to climb over all obstacles the islands and natives can throw at it. Nothing but armed men fighting in unison and accepting than most of them will die can repel an hungry Sea Abomination. Scholars from the Imperium speculate that the beast could be a remnant of an aborted Tyranid infestation millennia ago, since it displays chitinous protection on its head and back, and those appendages not unlike vestigial limbs.

But as monstrous as the Serpent is, the greatest danger in the tropical zone remains the battering storms which ravages the islands every year. Ionnacaira's rotation around its sun means that the tropical regions endure four local months of relative drought, with sparse raining, and sixteen of rainy season. During those long months, the natives come to fear the few days of blue sky, for during those, temperatures rose absurdly and dense black clouds quickly gather to birth storms able to engulf thousands of islands in its fury. The inhabitants are then forced to flee their coastal settlements to seek refuge inland, where the dense jungle can partially shelter them, at the cost of many lives as poisonous beasts and diseases ravages them.

Once the dry season returns, the humans of Ionnacaira starts their ferocious wars, the ravaged islands either seen as price worth taking now that their population are depleted or as a starting ground for the lucky survivors to start a campaign of subjugation against those who didn't share their plights. Tribal confederations rise and fall during four months of blood, the male captives ceremonially consumed by the victorious tribes to absorb their strengths and appease gods of the oceanic world.

It is because of all those dangers and wars that the Storm Angels settled on this world, and chose to uplift the savage natives to the ranks of Astartes, killing and dying for the Emperor and Sanguinius.

Recruitment
The Storm Angels recruitment method is as direct and brutal as the Astartes themselves. During the rainy season, the Chaplains are sent to investigate the tribes suffering under the worst storms, spying on them and stealing the children which display the greatest endurance and ability to survive in the deadly island jungles of Ionnacaira. During the dry season, it's the children showcasing the ferocious behavior in battle, those who kill and kill until they die on the battlefield which are spirited away to the Fortress-Monastery.

All those recruits are gathered at the Storm Cradle, where they receive the opportunity to become a Astartes -and more recently Primaris. The potential initiates are then brought to the Chapel of the Lost, where they'll have to endure for a whole day and the following night without sitting or falling asleep, while atrocious cries echoes from below and over them. Many aspiring youth will fail during this trial, and they'll be quietly taken away to be turned into the human servants of the Chapter, who will be hypno-conditioned to be willing to give their flesh and blood to their Masters when their dark needs arise.

Those young men who succeeded in this trial are then given a stone blade and separated in groups of two or three, depending of their total number. They then have to fight to the death, so as to insure that the strongest and deadliest recruits will be inducted into the Chapter. After this final trial, the recruits are brought to the Chamber of Sanguinius, where they are put into sarcophagus where the gene-seed of Sanguinius will be implanted into their bodies over several months and sometimes years, turning them into Primaris, since the Storm Angels have decided to slowly rebuild their forces with only this superior breed of transhumans.

Fortress-Monastery
The Storm Cradle is one of the mightiest bastion of the Imperium, a veritable fortress spanning thousands of kilometers of walls, tunnels, hidden traps and narrow passages were one Astartes can stop an army. This gigantic Fortress-Monastery was carved into and built over a whole island of Ionnacaira, one were storms are so frequent that no native ever managed to survive. Only the talents of the Storm Angel's pilots allow the Chapter to connect their fleet in geostationary orbit with their home.

At the heart of this immense demesne rest the Chapel of the Lost, the most sacred and secretive part of the Chapter's home. It is here that potential initiates are brought to endure their first true trial. But, unbeknownst to them, the terribly cries they can hear there are those of the brothers too afflicted by the Red Thirst to be allowed to leave their cells, but kept as a last measure, should Ionnacaira ever be invaded, to be let loose on their foes. The Sanguinary priests tolls day and night to try and find a way to calm the craving of those Brothers, to no avail.

Two levels over them is the Chamber of the Angel, where the ten members of the Sanguinary Guard stand in eternal vigil over the Chapter Master private quarters. Those legendary warriors, clad in gold and red Terminator Armors, equipped with jump-pack powerful enough to lift their hulking frames in the air, are ever ready to strike at anyone foolish enough to threaten their liege. In this gleaming chamber, where depictions of Sanguinius in his peaceful guise are watching over the pleaders, remaining all that the Great Angel wasn't only an Incarnation of War, but also a compassionate man.

Another important element of the Chapter's Monastery is its Great Hall, a large chamber, situated deep below the surface of the island, one of its walls allows to see the depth of the Ocean at peaceful time, only to be closed off by several meters of adamantium, ceramite and plasbeton if any danger is signaled near the Ionnacaira System. This beautiful room, large enough to accommodate twice the number of Astartes a Chapter is allowed, is littered with great status of ancient heroes from the Blood Legion of old and new champions of the Storm Angels, who died heroically serving the Emperor and Sanguinius.