Contrary to the common belief that "Sven Co-op" was developed to play through "Half-Life" cooperatively, Fearon had wanted to create a means for players to engage in cooperative experiences together, often just spawning in large number of enemies for them to dispatch together on a single map. This drew a number of amateur level developers to craft mission-based maps for the mod, where players would be required to go to different areas on the map based on success or failure of a given objective. Such designers included Dave McDermott, who initially ran the "Sven Co-op" website before becoming a developer on it. Fearon had planned from the onset to include support for cooperatively playing through "Half-Life"s single-player campaign within "Sven Co-op", but this was hampered initially by how the game's engine transitions from map to map that made it difficult to keep players together in the multiplayer approach. Ultimately, the team had been able to work this out, and later added support for "Half-Life"s two expansions, ', and '.