Looking through the Militarum Tempestus codex there are loads of regiments listed along with background information about them. The one which immediately cries out for attention is called the 'Alphic Hydras'. This regiment are very chummy with a certain Space Marine chapter (Ultramarines) and this association has led to them working alongside the; 2nd, 5th, 7th and 8th companies. Their association is so close that they have been granted additional training grounds throughout the Ultramar sector and to top it all off it has been rumoured that "some of the regiment's best young Scions have even been recruited by the Adeptus Astartes".
So, a regiment with the name 'Alphic Hydras' is acting very friendly with the chapter most despised by the Alpha Legion and they are now being inducted into the Chapter. If GW is doing what I think it is then I'm very pleased with this new chain of events. Roboute Guilliman wakes up only to find that half of his Marines are called 'Alpharius'.
