Super Mario World
Through ROM hacking, PangaeaPanga has made several difficult levels for "Super Mario World", the most famous of which is "Item Abuse 3". This level, which took three years to create and beat, has been described as "the hardest "Super Mario World" level ever". The level is impossible to beat without making use of tool-assistance to allow individual frame button input. PangaeaPanga has declared that "Anyone who can complete this is pretty much mentally insane."