EarthBound features five types of anti-piracy:

• First, it will simply check to make sure the cartridge isn't being used in a PAL console.
• Second, it will perform two SRAM checks at startup.
• Third, if the first two measures are disabled, the enemies on screen will be ramped up to ridiculous levels and you will find enemies in areas they don't belong in.
• Fourth, there's another SRAM checker that is called up six times during the game. Its purpose is unknown as of yet.
• Fifth and finally, if the game detects problems after Pokey turns off the Devil's Machine, the game will erase all of your save data and freeze, forcing you to go back to reset and find all of your work gone.