de Blob 2's story starts off with the central location, Prisma City, and its upcoming general election following the events of the first game. A mysterious priest called Papa Blanc deviously plans to rig the elections in order to gain power. Once successful, it is revealed that he is in fact working for the evil corporation from previous games, The INKT Corporation. With this success, he begins to drain colour from the cities as well as the inhabitants, in order to uniform the world in a total lack of colour and uniqueness. It is up to our hero Blob and the members of the Colour Underground to restore the city to its vibrant former glory. Blob frees the lands one by one, rescuing and reuniting friends along the way. It is his mission to restore the world to colour, free the population, and stop the mysterious INKT Corporation once again.
Unlike the original de Blob , the sequel on Playstation 3 features updated controls and gameplay mechanics. The same colour changing mechanics return, where Blob is given/finds a paint colour and absorbs it into his body. This leads to a platforming, sliding style of gameplay as he paints the world with various colours. A competitive multiplayer mode also makes its debut, where up to two Blobs fight to paint the world quickest and accrue points.
Compared to the previous title, de Blob 2 features more types of enemies, power-ups, and a higher resolution. Blob has a new dash attack to kill enemies and break through obstacles at the expense of paints points. Upgrades can be purchased by gathering inspiration points, including better defence and the ability to carry more paint. The game also introduces power-ups that turn him into a wrecking ball, provide unlimited paint, or transform the character into a black hole.