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Fearon was sent a copy of Half-Life by Valve prior to its official release, and as he started playing it, he had also begun toying with its programming, figuring out how to spawn enemy creatures in multiplayer maps.
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The game was originally created and released by Daniel Fearon Fearon at the time was one of the maintainers of the Half-Life fan website Atomic Half-Life created in anticipation of the game's release.
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The game can also be played in single player mode, taking advances of improvements over the original Half-Life that were made by the modifications, particularly for the artificial intelligence used by non-player characters. Multiple levels may be put together to make a longer campaign by the level designer. The modification was initially based around the levels from Half-Life, but since have expanded to include the other Half-Life games and user-made levels. The modification enables a server so many players can cooperate (along with and allied non-player characters) to complete levels against creatures and other enemies that are controlled by the computer. Sven Co-op is a first-person shooter based on Half-Life, using its GoldSrc game engine. The standalone release, representing version 5.0 of the mod, was released in January 2016. In 2013, Valve, which owns the rights to the Half-Life series, gave the development team the rights to publish the modification as a standalone title on Steam, and further allowed them to distribute the maps and assets of Half-Life to support its release. Since its original release, the project has been overseen by David "Sniper" McDermott.
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In addition to the cooperative gameplay, Sven Co-op includes improvements from the original Half-Life, including improved artificial intelligence for both enemy and allied non-player characters. The game, initially released as a mod in January 1999, and created by Daniel "Sven Viking" Fearon, enables players to play together on online servers to complete levels, many which are based on the Half-Life universe but include other genres. Sven Co-op is a co-op variation of the 1998 first-person shooter Half-Life. GoldSrc (heavily modified), Svengine (v 5.0+)
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