Press the flag then 'SPACEBAR' to start. Save the cats from dying by drawing them a safe line over the chasm. You cannot draw inside the chasm though so if a cat falls down, there's no saving them! At the end your score will show up. Also your ink can run out, so be careful!
It may have a few things that need improving so tell me what you think. Thank you to CodeClubRik for resources. Thank you to supersnookerboy for testing.