This technical demonstration presents the SuperStreamer project, which enables progressive game assets streaming to players while games are played, reducing the startup time required to download and start playing a cloud-based game. SuperStreamer modifies a popular game engine, Unreal Engine 4, to support developing and playing games with progressive game asset streaming. With SuperStreamer, developers can mark the minimal set of files, containing only the game content essential to start playing the game. When a player plays the game, these minimal set of files will be downloaded to the player's device. SuperStreamer also generates low resolution textures automatically when a developer publishes a game, and these low resolution textures are transmitted first into the game client. As players move through a game level, high quality textures required for the game will be downloaded. In our demo game, we are able to decrease the time taken to startup and load the first game level by around 30%.