Changes

====Prosperine====

With this stabilisation of the gene-seed, the Fifteenth Legion got its second chance. Recruiting from Prospero, they were able to rebuild their numbers – though they would never become numerous – and return to the Great Crusade, this time led by their primarch.

While little is known about how the Thousand Sons were organised before the coming of Magnus, it is recorded that they were not considered particularly different from typical Legiones Astartes apart from their psychic abilities (which resulted in the legion possessing the most powerful [[librarians]] of the era{{Fn|1a}}). When Magnus took command, his directions (influenced by his development on Prospero, as well as Prosperine culture itself) would cause some organisational and hierarchical changes within the legion. [[Chapters]] were referred to as '''Fellowships''' within the Thousand Sons, of which there were a maximum of 10. However, at the conclusion of [[Kamenka Troika|one particularly bloody campaign]], the Thousand Sons had lost almost 900 Astartes, effectively wiping out an entire fellowship. Rather than rebuild it, Magnus decided to reorganise and maintain the legion as 9 Fellowships, an organisation he referred to as the '''Pesedjet'''. Two special units were created within the legion, the elite [[Scarab Occult]] [[Terminators]] and the [[Hidden Ones]] of the [[Scouts|Scout Auxillia]]. The legion's command structure was adapted to include Prosperine philosphy in the form of the '''Rehati''' (the coven of Magnus), a second command-track in which the legion's senior officers were ranked according to psychic ability and influence.{{Fn|3b}}

The resurgent Thousand Sons brought their fair share of worlds into compliance with the Imperium of Man, and as such their main method of victory (diplomatic guile and trickery) was not questioned by the body imperial. However, as the Crusade entered wilder regions of space, more and more hostile forces were encountered that deployed powers similar to those that the psychic warriors of the Thousand Sons wielded. This, along with the ever-present rumours of 'witchcraft' and 'sorcery' surrounding the legion, resulted in [[Mortarion]] once more raising his voice in condemnation of the Thousand Sons.{{Fn|1a}} This time he was joined by [[Leman Russ (primarch)|Leman Russ]], whose long-held distrust of the legion came to a head after he witnessed the return of the flesh-change in the Thousand Sons during a joint action on the world of [[Shrike (planet)|Shrike]].{{Fn|3c}} It was decided that Magnus and his legion would be called to account, and the whole matter of astartes employing psychic powers at all would be ruled upon. This event was known as the [[Council of Nikea]], and at it – after much deliberation – the Emperor announced that no astartes must ever again employ the use of psychic powers, upon pain of destruction visited upon them by the Emperor himself.{{Fn|3d}}

*{{Endn|69}}: [[White Dwarf 469]], pg. 96

*{{Endn|70}}: [[White Dwarf 470]], pg. 105

**{{Endn|71a}}: pg. 92

**{{Endn|71b}}: pg. 100

*{{Endn|72}}: [[The Art of Clint Langley]], pgs. 84-85

*{{Endn|73}}: [[Master of Mankind (Novel)]], Chapter 5