Featuring the following heroine!

Nightshade

Real name: She went by Tilda Johnson in Power Man/Iron Fist 110.
AKA: The Queen of the Werewolves. Deadly Nightshade. Doctor Nightshade.

First appearance: Captain America 164
Favorite quote: "I want those motherless superheroes WASTED!" (Captain America 190. Nightshade finds the Falcon and Cap ... problematic ... during her United States takeover attempt, even after offering both of them the position of king. She likes to say, "Oh, poo" a lot, too.)

Team affiliation: Although she surrounds herself with males (human and otherwise), Nightshade's immaturity and penchant for throwing petulant fits when things don't go her way makes for frequent partner changes. She lost her werewolf-research-funding after pitching a temper-tantrum at the Yellow Claw, someone even Dr. Doom would treat with more care. Nightshade then tried to take over the United States using mind-controlled S.H.I.E.L.D. agents, but ran into Captain America and Falcon. Deciding a crime cartel might be more up her alley, Nightshade created the crime boss R. U. Rossum; alas, she annoyed Iron Fist by trying to off his partner Power Man and his girl Misty Knight, bringing her cartel career to an ignominious close. Using the Hulk to abscond with a computer override circuit, Nightshade brought the world to within three minutes of Armageddon when she accessed nuclear arsenals; this bid for power came to naught when a buncha super-heroes crashed through her hotel room. Her attempt at robbing high society with a group of other super-villains went bust when she tripped across her old playmates Power Man and Iron Fist at her first soiree, and then got stomped by debutante Millicent Hogarth. She returned to pure research (and werewolves) when she hooked up with the mystic Dredmund, but was herself turned into a furry creature of the night when her "babies" rebelled and demanded a cure.
Powers: Nightshade's peculiar control over men has been variously ascribed to a Meto-Probe machine, mesmer dust, and/or plain ol' pheromones. Strong minded types like Captain America are largely immune, although they can still fall prey to "illusions" she somehow creates. And -- this is a decided weakness -- whatever it is Nightshade uses to command men, it's negated by direct sunlight. In addition to charming (or drugging) males into doing what-ever she wants them to do, Nightshade is a biochemical and mechanical genius. However, her skills and intelligence have often been undercut by her child-like lack of maturity.

Favorite storyline: Power Man/Iron Fist 51-53. Faced with a decidedly macho mentality while building her crime cartel, Nightshade invents (literally!) a figurehead boss for her budding empire.

Least favorite storyline: Nightshade was an instrumental character in the much-reviled "Cap Wolf" tale, where she mutates Cap into -- well, a werewolf. It wasn't so much bad as it was silly; but then, these are funny books, right?