In the auto-scroll levels in the Mario games, how come there's still a time limit? If it's auto scroll, until the very end of the level when you get to the goal point, you're pretty much guaranteed to get to the end (or die) before running out of time, and before the "time running out" music begins. You can't really complete the level faster, and relatively can't pass it slower (well, you could possible go really slow as the screen slows). Is it hard to program the levels to not have a time limit when other levels do (and would it be harder than, say, the underwater level of Teenage Mutant Ninja Turtles being the only level with a time limit)?