SiN Episodes is the title of a planned series of episodic games for the PC that would have expanded upon the 1998 computer game SiN. A total of nine episodes were planned with only the first one released. Developed by Ritual Entertainment and powered by the Source engine, the first episode "Emergence" was the first computer game by a major developer to both be produced episodically and delivered over the Internet without the intervention of a publisher. This was accomplished through Valve Corporation's Steam content delivery system.