Tasty Planet

The plot is shown solely through comic strips at the end of some levels. The first comic strip shows a scientist telling his assistant about his latest discovery, the Grey Goo bathroom cleaner. They place it under a microscope, and the first level of the game begins. After the first two levels of the game, the assistant touches the Grey Goo, who bites him and enters his body. The scientist tells his assistant "Just go and wash your hands."

The Grey Goo is then washed down the drain and lands outside, where it moves to a park and grows in size. It then moves on to a picnic table where the scientist and assistant are having lunch. When they discover it, the pair throw the Grey Goo into the ocean. The Grey Goo then eats through the ocean and is launched by a whale into another park and then to a city. There, the Grey Goo faces its first war from humans, who attempt to use guns, tanks, etc. to stop it. It eventually launches itself into the sky and then into orbit around Earth. After eating the moon, Earth, and the rest of the solar system (including Pluto), it moves on to nearby stars like Alpha Centauri and beyond the Milky Way. However, its mass becomes too great after devouring the fabric of space and time, and it implodes thus causing the universe to begin again.

Tasty Planet is split up into 9 chapters, each containing a depending number of levels. They are listed in increasing size order as the Grey Goo grows.

They are Labs, Outside, Picnic, Ocean, Park, City, Sky, Orbit and Cosmos.

An additional option selectable from the main menu is the Endurance mode. These are variations on 3 existing levels. The only change is that the player grows extremely slowly, and it can take over an hour to beat one of these levels. They are considered the most difficult part of the game.

Just like in the original Tasty Planet game, the plot is shown solely through comic strips at the beginning or end of some levels. The first comic strip shows a scientist telling his assistant about his new time machine, and also mentioning an accidental discovery, a grey goo blob that is sitting under a beaker. The assistant thinks the blob looks hungry and gives it some candy. The blob eats the candy, then the scientific apparatus on the table, followed by rats, then cats, then larger apparatuses, until it is big enough to consume the time machine itself, which makes it travel back in time 65 million years.

The Grey Goo starts small again in the late Cretaceous period, consuming the plants and animals of the area, before consuming a volcano and being hit by a meteor, which prevents the dinosaurs from going extinct. In the present, the scientist and the assistant experience changes in the timeline as they happen in the past. After being hit by the meteor, the grey goo travels through time again, but each time it travels through time it reverts to a small size. It then travels to Egypt, and consumes snakes, mummies, cats, people, buildings, and the pyramids. Next, it travels to Ancient Rome, where it consumes a feast, people, then buildings and destroys the city, forcing the Romans to pull together and prevent the fall of the empire. Next, it travels to Feudal Japan, where it eats rice, ninja, and buildings, but also consumes Monsterzilla, removing the world's protection from giant monsters and allowing them to ravage the present. The scientist by this point has figured out that the grey goo has only one jump left, this time to their future, and they must be prepared for it, so he and his assistant preserve their brains so they can survive until the grey goo appears. When it does, far in the future, it is microscopic instead of a few centimeters in diameter as when it usually jumps, but the scientist has prepared tiny robots to destroy the grey goo while it is still small. However, it evades the bots and grows larger, necessitating the scientist's second line of defense: energy weapons grafted onto ants, rats, and cats. It evades those too, growing large enough to consume the scientist and his assistants' brains. Giant humanoid tanks armed with powerful lasers are dispatched to destroy the goo, now several meters in diameter, but it evades the blasts, consumes future technology, people, and cars, and destroys the tanks too, destroying the city. Next, it launches into space, grows on small asteroids, destroys humanity's last line of defense - armed circular satellites that measure roughly 120 kilometers in diameter - then moves on to destroy Earth, the moon, and the planets (excluding Pluto as it is too small compared to the gas giants). Next, the grey goo consumes small stars around the sun, then the sun itself, working up to red giants. The goo eats the largest stars (red hypergiants); though one of them undergoes a hypernova leaving a black hole, the goo consumes the black hole as well. The goo continues to consume nebulae, star clusters, galaxies, and galaxy clusters. Ripping through the fabric of time, it eats said fabric and discovers that the space-time continuum is resting on the back of a turtle, which is on the back of a slightly larger turtle, and that it's turtles all the way down. It then eats the turtles until they are gone, but since the turtles are infinite, the goo's feast is never-ending, then the game is over.

Tasty Planet: Back For Seconds is split up into 6 chapters, further split into 48 levels. They are listed largely related to the story, but many of the levels are separate challenges unrelated to the growth of the grey goo, such as a level where the goo must eat hippopotamus babies but avoid the adults until it is large enough.

1. Modern Era (4 Levels)
2. Cretaceous Era (7 Levels)
3. Egyptian Era (11 Levels)
4. Ancient Rome (8 Levels)
5. Feudal Japan (7 Levels)
6. Far Future (10 Levels)

The game begins in Paris, France. Two chefs, which resemble the original scientist and his assistant from the two original games, think that the kitchen is dirty; the older chef informs his assistant of a robotic cat gifted to him by his cousin. They order their robotic cat to consume peas, cockroaches, mice, wine bottles, knives, and croissants on the floor. However, it did not stop and it continued to eat more. After eating waiters, customers, and more people, it started to consume trees, cars, buildings, the Eiffel Tower, and eventually all of Paris.

An infant octopus in the Caribbean Sea is sleeping, only to be awoken by an aluminum can that hits its head. It swims to the surface of the sea and, much to its dismay finds that a city resort on an island has produced a large pile of waste. The octopus starts to eat rubbish, causing it to become larger and consume the waste-producing island resort.

In Africa, a foreign stray rat appears among other rats trained to eat old land mines to prevent the deaths of endangered animals. The rat begins to eat inhabitants and fauna of the Sahara Desert, along with safari vans, resorts, and planes.

To prevent the collapse of endangered bee colonies, a genetically engineered bee is kept in a test tube to be tested. During an interview, a man walks by and observes the bee. Shocked with the size of its eyes, the man aggressively snaps the test tube, causing the bee to eat nectar at first, but grows in size and eats gnats, apples, drones, then whole humans, trees, aircraft, buildings, hills, mountains, and islands. Finally, the bee consumes the continents, the Moon, and Earth.

In an alternate timeline, a man in charge of a large fishing business boasts about having killed all basking sharks in the Pacific Ocean when the year is 1956. However, one off the coast of British Columbia begins to consume other fish, scuba divers, and eventually log cabins.

In the Australian Outback, a stray dingo trained to eat invasive species begins to consumes humans and eventually the entire landscape, including tractors, houses, and crops.

In the future, most of the ice on Earth has melted, resulting in a sea level rise. A group of penguins has been confined to a barren island, while most of humanity has built a floating island in the highly polluted atmosphere. A mutation occurs within the commune of penguins, giving it wings that it uses to fly to one of the artificial floating cities. It begins small by eating first french fries, meat snacks, moths, and butterflies, before consuming air conditioning systems, buildings, futuristic flying vehicles, and entire floating cities.

In 2057, the first humans are finally able to land on Mars. However, one of the crew members reports observing "anomalies" in the ice samples he had brought with him. The "anomalies" turn out to be from a grey goo frozen in the ice, which is subatomic in size. The goo begins to eat quarks, hadrons, atoms, before growing in size to eat the crew members, their robotic canines, and their settlements on Mars. After consuming all of the human bases, the goo consumes the surface features of Mars (such as the planet's ice caps) before consuming the entire planet and the seven other planets in the Solar System (including Earth and excluding Pluto). It then moves up in scale to eat the Sun, M-type, K-type stars and yellow dwarfs, T Tauri stars, nebulae, "Space Manta Rays", the Milky Way and other galaxies in the Local Group, a "Noodly Monster", and eventually the observable universe. The universe, however, turns out to be nothing but a quark in a much larger universe, with other parallel universes being other quarks in the larger universe.