The Blood Hounds
My homebrew (obviously) called the Blood Hounds, they are a renegade loyalist chapter, having been created in secret somewhere right before the horus heresy, they are unknown in which primarch is their father, though it is rumored they were the first to be called the "chimera" legion, it is suspected by most that they have the geneseed of Angron and Sanguinius. They have the natural ability to track down enemies with almost supernatural accuracy, they are rather large, (bulky) and have quite the bipolar temper. They have recently just resurfaced after an extended sailing in the warp.
They specialize in Bolters and hand to hand combat (like with their fists) the latter they actually prefer. I hope you like them.
Ps: enjoy the cinematic images.