Alyx Vance is the daughter of Eli Vance and the female lead in Half-Life 2. Eli was one of the scientists present when the anti-mass spectrometer set off the resonance cascade in the original Half-Life. He escaped with his life and his little girl and managed to survive the next ten to fifteen years among portal storms and the seven hour war. At the same time Alyx grew to maturity in a world that mankind had completely lost control of. The particulars of Alyx's life during this tumultuous time are unknown but she clearly adapted quickly.
When Gordon first meets her she's saving his ass from a brutal beating at the hands of Civil Protection. From there she guides you to the resistance's base for City 17 where their attempt to teleport you out of the city fails rather spectacularly. After a harrowing adventure involving much death and many explosions you reunite with her in the hidden resistance base. This lasts all of ten minutes before violent circumstances separate you once again. Eventually, you meet up again and the two of you take down the Combine with the power of friendship and high energy physics. Alyx remains your companion through Half-Life 2: Episode One and Half-Life 2: Episode Two following you through and under City Seventeen and White Forest.
As a partner she is actually useful, shooting at foes, warning you of danger, and just breaking the silence with the occasional wry comment. She also tells you to hurry about a million times toward the end of Episode Two, but nobody is perfect. As a person Alyx comes off as an extremely competent character that retains a believable level of frailty, both emotional and physical. She holds herself together surprisingly well in what are outright hellish conditions but has more than a few moments where it's very clear that the death and fear surrounding her are taking their toll. By that same token Alyx can die if she takes enough damage in a short enough time and that is an automatic fail for you. Luckily her health regenerates really quickly. So long as you take point and don't let her get mobbed this almost never comes up.
Lastly, as a character Alyx is an attractive young woman. But not too attractive. Video and computer games, particularly gory shooters, are aimed squarely at teenage and twentyish males and it's just as much an industry standard in gaming as it is in Hollywood to make the lead lady major eye candy. The fact that Alyx is just sort of attractive and wears jeans and a leather jacket that are form fitting but not particularly revealing or sexy is a real point in Valve's favor. Combine that with her cheery personality and actual usefulness across a variety of situations and I found myself feeling genuinely fond of her. It's really rare that a game can actually trick me into thinking of a character model and some hundredish voice clips as someone rather than something but Valve managed it in Alyx Vance.
10/10. Would go hunting head crabs with again.
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