It's an achieveable ending--one not planned by the coders, but one nonetheless. You cannot play past that point.
A couple of old arcade games have "kill screens", such as Pacman and Donkey Kong.
A couple of old arcade games have "kill screens", such as Pacman and Donkey Kong.
It is technically possible to go up through level 255 at which point it loops back to 0. It's been done through a tool assisted run (carefully doing inputs frame by frame rather than playing in real time)
All that said, I feel a bit weird telling a community I don't belong to that they're incorrectly enjoying a game I don't play.