There she is audio - Abyss mod for Portal 2

In an alternate universe, set during the Seven Hour War, you find yourself plunged into the depths of an abandoned Aperture facility. Abyss explores the failed ambitions of the once-flourishing company, and the legacy it left behind. As the war rages above, you as the player will be confronted not only to the imminent danger it poses, but also to the existential nightmare from which it all started as you are taken deeper into the facility than ever before. Your choices have consequences, and your actions dictate your survival -- or lack thereof.