Syphon Filter Totally Unauthorized Strategy Guide - Bradygames Strategy Guides Author:BradyGames Resembling Metal Gear Solid with its covert missions, stealthy actions and hi tech arsenal, this game includes a step-by-step walkthrough for all mission objectives, and level maps to uncover the location of important weapons and other items players need to survive. Playing as Gabriel Logan, players must stop an unknown terrorist group before th... more »ey can use the deadly new biological weapons known as "Syphon Filter". Players are taught the pros and cons of each weapon, what is good in particular areas or for one-shot kills.« less