Canis Helix - Effects: In reality, those aspirants who are likely to fall prey to the Wulfen mutation inherent within the gene-seed of Leman Russ do not do so after immediately imbibing the Canis Helix mixture, but usually over the solar weeks and months of training that follow.After the aspirants are taken through the Gate of Morkai, a mystic portal deep within The Aett (The Fang), the Space Wolves' massive fortress-monastery, where every aspirant's mind is picked and probed by the Chapter's psychic Rune Priests (Librarians) for signs of corruption or mental weakness that will make them easy prey for the blandishments of Chaos, they drink from the Cup of Wulfen.One of the most important aspects of this test is that the aspirant show himself able to keep this bestial side under control, even while making his way through the Fenrisian wilderness in harsh conditions. Those that fail to do so will transform into Wulfen, and remain in the wild.If the aspirant returns to The Fang from this so-called "Test of Morkai," he is implanted with the remaining components of the Space Wolves' gene-seed, which stabilise the mutational effects of the Helix.Although this procedure is extremely hazardous, the remaining components of the Space Wolves' gene-seed will prove ineffective at initiating the metamorphosis into an Astartes unless the Canis Helix is implanted first to serve as a catalyst for the transformation.The next phase of the neophytes' transformation into a full-fledged Space Wolf is a trial period of training in which the physical transformations initiated by the genetic catalyst within the Canis Helix begin to manifest themselves.Amongst the most common changes are that the neophyte's senses will become vastly superior to even that of other Space Marines, his teeth will lengthen into fangs capable of tearing through plasteel, and his skin will toughen to the texture of leather.His body mass grows by up to eighty percent and many of his bones fuse. Most of the aspirants will continue to grow into their newly-received genetic implants whilst others succumb completely to the Curse of the Wolf at this time and devolve into one of the giant, feral and bloodthirsty mutants known as the Wulfen.To become one of these fell creatures is to fall from the Emperor's grace, and to roam the wilderness of Fenris forevermore as a creature of the darkest night.The Space Wolves' harsh induction regime generally ensures that these individuals perish at an early stage in the process. However, at the time of the Great Crusade, when the Emperor and His Astartes Legions were conquering vast swathes of the galaxy in the name of Mankind, those brothers touched by the Curse were banded together into the 13th Great Company, where their feral ferocity could be brought to bear en masse, as well as contained for the safety of the whole Legion. But eventually the 13th Company disappeared, their loss the subject of numerous myths.Even once the Canis Helix gene sequence has been stabilised within the body of a neophyte, it still has the power to affect the warrior throughout his life, particularly when the ferocity of the Space Wolf, barely contained at the best of times, is roused in battle. Then the warrior may finally succumb to the Curse of the Wulfen, and he will be transformed once again into the beast he has fought for so many standard centuries to subdue.It falls to the Wolf Priests, the cult leaders and spiritual guides of the Chapter, to keep the Curse of the Wulfen from overtaking the Space Wolves, and they take full responsibility for the development of their charges, be it martially, spiritually or mentally. Those that are "Wolf Bitten" (suffering from the Curse of the Wulfen) are given over to the care of the Wolf Priests.As Space Wolves Astartes grow older and more experienced in battle, the Canis Helix causes additional physical alterations: their hair turns grey, their fangs grow even longer, their skin becomes even more leathery, and, in some rare cases, their eyes turn yellow. A Space Wolves Astartes who reaches this stage is considered fit for elevation to the rank of Grey Hunter.In some Space Wolves, the Canis Helix leads to the development of a brooding, malignant demeanour, which makes them unfit for the camraderie normal to a Space Wolves pack (squad). These Astartes traditionally have become Wolf Scouts.By the time Space Wolf Astartes are considered fully mature, the Canis Helix has caused their canine teeth to elongate into true fangs and their hair to grow long, shaggy and grey, at which point they join the ranks of the Long Fangs, the Chapter's Veteran heavy weapon specialists.It is speculated, though not known for sure, that some latent genetic irregularity in the Canis Helix accounts for the unusual, elemental-based psychic abilities of those Space Wolves who eventually become the Chapter's Rune Priests.