Tasty Planet: Back for Seconds is a top-down video game published by Dingo Games in September 2010. It is a sequel to the 2006 game Tasty Planet. The game is targeted at ages 8 years and older, and may be downloaded to Windows or Macintosh systems.
Tasty Planet: Back for Seconds is game focused on the growth of a self-replicating blob of nano-machines, "Grey Goo." The levels follow the Grey Goo as it changes from eating dirt particles to bugs and leaves, and then eventually the rest of the universe. The game is arcade in style, and has both a casual mode, where players can play for leisure without a timer, and the full game which is timed and must be completed before the time runs out to complete the level. There are also bonus levels for each mode which are both unlocked only after completing the timed mode, and the game has a two-player, where both players share in the gray goo's growth.
Source: Wikipedia, "Tasty Planet: Back for Seconds", available under the CC-BY-SA License.