GOOOOO YOUUUU FACKKK
The Higgin's bloodline is the European ancestral bloodline of members of the Lords of Alchemy. Those of this bloodline are adept and capable of performing magic such as alchemy and enochian magic and are high ranking members of the Lords of Alchemy.
Years ago, the Lords of Alchemy plotted to create a goddess capable of re-creating the world. A plan was formulated by the Lords of Alchemy's head of R&D, Cliff, to use a woman named Saya to create a goddess. Falling in love with her twin brother Theodore, the both of them rejected the plan and ran away. The two later got married and had a child named Canna. Continuing to oppose his brother's plan, Theodore and Saya are both killed by Cliff though he resurrecting the latter, erasing his memories, and controlling his body though an AI as part of his plan of using Canna.
Alongside their organization, Ashtear and Cliff begin to perform their plan of creating a goddess using Canna. When Ryu Hayabusa intervenes during their terrorist attack in the United Kingdom and is intentionally cursed by the Regent into the Grip of Murder, Cliff takes advantage of the situation and gets a sample of his DNA. Combining it with his bloodline, he creates a clone of Ryu, Epigonos.
Eventually, Ryu learns of Cliff's true allegiance when he encounters Cliff and Ashtear during his mission to Antartica where he also reveals of him using Ryu's DNA. When Canna is taken by the LOA and Ryu attempts to rescue him, he battles the Regent and is revealed to be Canna's father after delivering a seemingly fatal blow. Cliff then explains his plan and extracts the purified form of the Dragon Sword. Due to the containment unit in which she was placed in, her anger towards Ryu, and exposure to the Dragon Sword's purified form, Canna transforms into the Goddess..
Later, Cliff is defeated and killed from a combined assault of Ryu and Theodore, whom had survived his battle and regained his memories. In order to dispel the grip of murder on Ryu, he forces Ryu into a battle in which he delivers a mortal wound (a requirement to undo the curse) and leaves him to save Canna. Ryu is able to defeat the Goddess and save Canna in the process.