When I first heard about it, I didn’t even know it was possible for a Super Nintendo game to do such things outside of region locking. Earthbound does multiple things to make sure you’re playing the game legitimately.
The first line of defense is not out of this world, it just makes sure you’re playing it in the correct region for your system.
Part two of the copy protection comes when the game checks for SRAM. Anything more than 8kb gets you trouble with this screen below.
Phew … two different and separate tiers of copy protection. That’s got to be enough! Wrong! If any of the above features are disabled, the game will eventually notice that the programming has been changed and increase the number enemy encounters in numerous areas! This is sure to make a playthrough harder and much more frustrating.
If that’s not enough to thwart potential pirates, the programming within Earthbound supposedly also checks multiple times while you’re playing, so parts one and two could possibly be implemented at any time. If the third zone of protection isn’t enough to scare you away, there is one last trick the game will pull.
After you finish the final battle, the game will freeze just before the ending. Upon resetting, you will find all your save games erased. The video below details the steps of Earthbound’s copy protection as well as the final tier in action.