Special Rules: The only Code permitted is the one that allows you to access Hard Mode. This is done by holding Select until the word Hard appears under the title. This is entirely optional. Your scoring attempt ends when your lives run out OR after you defeat the Final Boss for the first time. It's possible to die after delivering the final blow, allowing you to defeat him again and again. This is due to the fact he's worth 100,000 points, which is worth multiple extra lives.
No excessive leaching; you only have three minutes to beat a boss for example.