City17: Episode 1 or shorthanded as C17ep1 Is a mod being developed by the Gear Development Team. It is a single player Modification, that plans to include the player within the Half Life 2 World, and scenery's that Gordon Freeman and Alyx Vance Both travel to. Episode 1 is the first in a trilogy that hopes to span across Half Life 2: Episode 1, towards Half-Life 2: Episode Three. C17, will be a host to many new features under the Source Engine, including the SE2 and in-built LUA for various graphical effects. C17 requires that the player, have Half Life 2, and the newly added Orange Box SDK Base.