Spy, also known by his codename Loki, is a character B.J. faces in Wolfenstein RPG. He is a double-agent working for both Nazis and Allies, but is willing to help B.J. However, the two dislikes each other for being "different" kinds of agents. This mutual dislike is culminated when both agents have a hand-to-hand duel in Castle Wolfenstein. When defeated, the Spy runs away with B.J. looking forward for a rematch. However, Spy is actually willing to help him to prepare for a battle with a demon summoned by Nazis later. Before the final battle with Harbinger, the Spy advises B.J. to find the Spear of Destiny, before leaving. While he is still willing to have a rematch with B.J. someday, the Spy finally learns to respect the agent.
The fight with the Spy is one of the hardest of the game and is more of a puzzle then an a common fight. The best strategy is to explore environment for power-ups and serums, don't touch spiked walls, and kick Loki into fire pits (position yourself so a blowing drum would be behind you, so Loki can't kick you off your position, and kick him into the pit that should be two squares in front of you).