Rachel Van Helsing
First appearance: Tomb of Dracula 3. She died in Uncanny X-Men Annual 6...well, actually, being a vampire she was already dead, but you know what I mean...
Powers: Rachel was a normal human for most of her tenure in the Marvel universe. She was an anthropologist who was also a parapsychology expect. On her vampire-hunting expeditions she carried a cross-bow.
History: After witnessing Dracula murder her parents, Rachel developed an obsessive interest in hunting down the Lord of the Vampires. Raised by vampire hunter Quincy Harker, Rachel spent much of her young adulthood in extreme peril as they raced around the world in pursuit of Dracula. In this they were joined by Frank Drake, a descendent of Dracula. Harker was killed in an abortive attempt to off Dracula once and for all. Rachel, fearing she was losing her humanity, broke up with Drake and gave up the hunt--only to have Dracula track her down and turn her into a vampire. Rachel "lived" (so to speak) as Dracula's consort until he tried to recruit Storm. The X-Men rescued Storm, and Rachel shook off her brainwashing long enough to impale Dracula. Not wishing to remain a vampire, Rachel asked to be killed. Wolverine, saying killing was his job, was of course happy to grant her request.
Current status: Although the vampires for a time disappeared from the Marvel universe, Dracula and his evil kindred are back. Rachel, however, remains dead.
First appearance: Avengers 57
Powers: The Vision is a synthezoid, a synthetic being who is none-the-less every inch human. He has absolute control over the molecules of his body. He can became intangible enough to float, or increase his density until he weighs several tons. If he partially solidifies in a living body, he can knock out or even kill his target. He is powered by solar energy through a gem set in his forehead; he can also focus energy through the gem to unleash a bolt of solar energy.
History: Programmed by Ultron to destroy the Avengers, the Vision proved too independent for the task set him. As they investigated his origin, the Avengers discovered that the Vision had been given the mind waves of the then-late Wonder Man as a personality template, and that his body had a previous existence as the Human Torch. Though artificial, the Vision is capable of human emotions. He married the Scarlet Witch, with whom he had two children. The children, however, have been lost in the time-stream and perhaps never existed as real beings. The Vision himself was dismantled by the U.S. government; the best efforts of the Avengers could not restore him, physically or mentally, to what he had been before. He and Wanda grew apart, and eventually divorced. Captured by Proctor's Gatherers, the Vision was transferred into an alternate Earth version of his pre-dismantled body.
Current status: Vision remains a stalwart member of the Avengers, although questions about his origin, his children, and his relationship with Wanda are still unresolved.