The run begins as soon as the new game is started and it ends as soon as the final boss is defeated.

After my first run, a glitch was discovered allowing Asterix and Obelix to do another double jump after making an attack. If the glitch is used well, then it is possible to do as many double jumps as possible.

It's a pretty difficult glitch to master in the long run, and it took me a whole year to more or less manage to complete the game without missing out too much.