A vampire the old families look down on, who decides to stop asking for their permission and take the whole species somewhere new.
Deacon Frost is an upstart vampire with great ambitions and influence, the primary enemy of the first Blade and a man who wants to conquer the human race. Stephen Dorff plays him. The club Blade raids in the opening minutes is his.
What sets him apart from the vampires around him is that he was made, not born. The pure-blood elders consider Frost and his kind socially inferior, and when he tries to push them into a war with humans, they rebuke him. His answer is to stop asking. He has an elder stripped of his fangs and burned by the sunrise, strips the rest of their authority, and imprisons them.
Minor spoiler
Frost’s plan is a ritual: twelve pure-blood vampires, and Blade’s blood as the key, to awaken the blood god La Magra. When Blade goes to rescue Karen from Frost’s penthouse he finds his own mother there, alive, and Frost reveals that he is the vampire who bit her the night Blade was born. It is the film’s central twist, and the reason the reader who sent this list described him as the man who killed and turned Blade’s mother.
He completes the ritual and gets the powers he wanted. Blade cannot beat him until he reasons that the body is still a body, and gives Frost an overdose of the anticoagulant EDTA, which reacts with vampire blood. Frost swells into something grotesque and explodes.