Pac-Man Planet Eater
In the early days of Pac Man, Pac was always contained within a ROM chip. Now and then he would be release from the ROM to run around a maze eating various sorts of pellets for a while until either the power was cut, or the game would reset him back to the chip.
Pac Man's life continued like this for decades, although moving from one platform to another, he was contained to short bursts of feeding frenzies. However with the popularization of the internet an online version of Pac Man was launched. This new Pac Man knew no bounds, he was not limited by time, and was able to continue his feeding frenzy until today.
The uncontrolled calorie intake of Pac over the years eventually grew him into a massive monstrosity, and as he grew so did his appetite, the exponential growth of his all consuming mass is now beyond containment or control. Our solar system will be the first to fall, but no where in the universe will be safe for long.