19. Alyx Vance (Half-Life 2 series)
One of the first things I like about Alyx is how she's designed. So many video game companies treat gamers like sex-driven idiots that need a chick with big boobs if the company is gonna put a female character into a game. Or if she doesn't have big boobs, she has to dress provocatively or act provocatively. Alyx isn't like that, and it's refreshing to see a female lead actually look like she belongs in the world shown in the game. Alyx is still hot, but everything from her jacket/t-shirt combo and jeans, to her admittedly bad haircut makes her look like a real person, who happens to be attractive, living in a post-apocalyptic world. And beyond that, I like her character. She's feisty indeed, and able to kick Combine ass rather efficiently the first time you meet her, and over time, she kinda acts as Gordon's guide through the world that he's just seeing for the first time. And honestly, I like the development of a relationship between Gordon and Alyx too. It doesn't feel as forced as love at first sight like in RPGs. She's friendly to him at the start based on reputation, and when she sees him in action, being a hero (hell, he brings her back from the dead), she winds up falling for him (although she's still a bit too shy to truly admit it). Overall, I find her to be a fascinating character, unique as a female lead, and I like her for it.