Caelus Prime

Caelus Prime is an Imperial Feral world and Homeworld of the Nemean Lions Adeptus Astartes Chapter.

History
Imperial Cartigraphicae records indicate that Caelus Prime was rediscovered by Rogue Traders during the Great Crusade. Several times larger than Terra, Caelus' landmass is composed of three super continents with vast plains stretching to the horizon. No records remain to reveal when the original human settlement took place or at what point they reverted back to a tribal society. The origin of Terran-like animals living alongside the indigenous fauna is likewise a mystery lost to time.

Caelus Prime is a Feral world--with human tribes spread across the planet. The Nemeans -as they call themselves- are a nomadic people with a strong warrior culture. From a young age they participate in ritualistic hunts to gain pelts.

Notable Animals
The Nemean Leonis, while extremely similar to its historical ancestor the Terran Lion, has some key differences, for one its far greater size. It has diamond edged claws that are known to be able to pierce adamantium armour. However particularly notable is its infamous hide. Made from a collagen material the hide is highly resistant to damage, and it only gets stronger with age. Indeed this hide is what ancient Leonis, known as Apex are famous for as it makes them nearly invulnerable. Upon reaching a certain age and size the collagen undergoes molecular conversion into a bone skin hybrid. This skin is many magnifications more resistant to damage, to extent that conventional weapons, even bolters, cannot break it. This fact, coupled with the size and prime nature required before this mutation, makes the Apex Leonis exceptionally dangerous to hunt, something that even experienced marines will think twice on.

Fortress-Monastery
The Nemean Lions' Fortress-Monastery is Mytikas Peak, positioned on a plateau overlooking the great plains of Thriasia, ancestral home of the original tribes. A sprawling network of the usual Astartes defences rings the perimeter and indeed from the outside the Fortress Monastery is a typical example of an Astartes fortress. Deep within the heart of the defences however is an enormous underground structure, a vast bunker that the Lions call home. It contains an extensive array of holo projectors and atmospheric processors to simulate the appearance of the plains that lie outside the many layers of stone, metal and shielding. Hundreds of tents, identical to those used by the tribes of the plains (though substantially larger), dot the artificial plain, allowing the Lions to continue to exist as they did prior to becoming Astartes and maintain the traditions that are deeply ingrained into their core while still being as well protected and safe as any other Chapter when it returns home to rest and rebuild after campaigns.