The player character — de Blob — starts out as a ball of clear "water". de Blob is free to roll around and collect paint from Paintbots in the three colors of red, yellow and blue, which can be combined into green, orange, purple and brown. de Blob then merely has to touch a building, lamppost, billboard, or other object for the entire surface of said object to be smeared in his current color. As he colors the city, the game's soundtrack, featuring live bands which recorded slow and fast versions of each "lick" (each hit), gradually adds more instrumentation as well as an additional "layer" of sound corresponding to de Blob's current color—being red usually adds a saxophone solo to the music, for example. As de Blob collects paint, his size increases to a maximum of 100; each object he paints costs a paint point, as does attacking enemies, while touching water makes de Blob remove his color.