Based on a pen-and-paper, vampire-themed role-playing system from White Wolf Games, Bloodlines is the second game to be released using Valve's shiny new Source graphics engine. While it's not the prom-queen stunner Half-Life 2 turned out to be, it's a deeper and more adult RPG with much to recommend it. If it was as stable as it is involving, then we'd have a classic on our hands, but even with its flaws, it's highly recommended.