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 console version the sequel is multi-platform. As such the controls have been wildly updated, no longer making use of the Wii motion controls, in favour of a more standardised console control scheme. The same colour changing mechanics from the first game return, Blob is given/finds a paint colour and absorbs it into his body. What follows is a platforming, sliding style of gameplay as he paints the world these various colours. Another first for the series is a competitive multiplayer mode, where up to two Blobs fight to paint the world quickest, and accrue points in doing so. The game can also be played cooperatively with the character Pinky who provides assistance.
Compared to the previous title there are more types of enemies, power-ups and the game runs in 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 power-ups turn him into a wrecking ball, provide unlimited paint of all colours or a hazmat suite, or transform the character into a black hole. There is more emphasis on the platforming elements. Blob can enter buildings where the game turns from 3D to 2D. Different platform challenges need to be completed before a building is fully taken.