Opposing Force CTF throws players into the classic confrontation of Soldiers vs. You can fly around and explore if you are unfamiliar with the map. When you first enter a CTF game you will be in spectator mode. When creating a game, do so as if you're creating a deathmatch game, but choose a CTF map. To start or join a CTF game, navigate the multiplayer menus (as described on ) and choose a game running a CTF map (designated with "op4ctf_" in the map name). The team who captures the most flags is the winner - but there are many other goals to strive for in OpFor CTF! Joining or Creating a New Game The goal in Half-Life: Opposing Force Capture The Flag (OpFor CTF) is simple: Capture the opposing team's flag and return it to your flag in your home base.