This week,Eurogamer spoke with a video game legal expertto confirm that the sanity effects Nintendo had patented forEternal Darkness: Sanity’s Requiemare, in fact, a part of the public domain and able to be used by all game developers without fear of legal repercussions. Nintendo’s patent expired in 2021, so now it seems to be open season for anyone looking to try their hand at making third-wall-breaking sanity effects based on modern gaming hardware.
It’s an amazing gimmick, but after Eternal Darkness, Nintendo hasn’t really touched the horror genre at all, so this fantastic mechanic has been underutilized and nearly forgotten.

Luigi’s Mansiondoes not count as Nintendo making horror games.
Now that the mechanic is in the public domain and, according to Eurogamer’s legal expert, developers “shouldbe able to use whatever elements” they want, I’m ready forevery horror game to start using Eternal Darkness’ sanity effects.
The Sanity Effects We’ve Been Missing Out On
Plenty of horror games have sanity effects. The Amnesia series, Fear and Hunger, and Darkest Dungeon all require the player to take care of the protagonists’ mental health. If the sanity meter gets too low, the character will suffer various conditions: seeing things that aren’t there, falling into despair and losing the ability to attack, or just flat-out dying.
Eternal Darkness’ sanity meter operated in a much different way. The game introduced meta elements if the player’s sanity got too low by displaying quick videos of their save file being deleted, rooms would be flipped upside down when you walk into them, your head would sometimes just explode as your headless body continues to roam around the environment,the TV would mute itselfand the HUD would display common TV UI even though you didn’t touch the remote. It was a really cool concept that kept the player on their toes.

Even though it was obvious after a second or two what was going on, the sanity effects caught a lot of people off guard. Even when you know to expect it, their varied intensity can still be shocking.
Sanity Effects For A Modern Era
Unfortunately, Eternal Darkness was a GameCube exclusive, and there’s no way to play it on modern hardware (unless it ends up being added tothe Switch 2’s GameCube collectionat some point down the road). We need new developers to update and modernize what Eternal Darkness did all those years ago.
Because so many of the sanity effects from Eternal Darkness were tied to the then-current gaming hardware of the time, like memory cards and CRT TVs, it would be neat to see what developers can do with the technology of today. Imagine suddenly being thrown into the PlayStation settings menus where you’re told that the save files forallof your games have been deleted. Or seeing the villain watching you - not your character,you -on a security monitor, the feed coming from your own Nintendo Switch 2 camera.

There are so many ways to play with the complexity of modern consoles. One second it seems like your PS5 has lost power, and when you get to the boot-up screen, an error message tells you that your system is corrupted and is officially bricked. As you start to panic, a message pops up saying “just kidding,” and you’re thrown back into whatever psychological experience you were just in.
It’s always a shame whenever a publisher patents a game mechanic because it means that great ideas can’t be iterated upon. Even though it’s in the public domain, I imagine we might not see a ton of studios jumping to use Eternal Darkness’ sanity effects to avoid any legal issues with Nintendo, since fair use law is a little murky. I hope I’m wrong, andBloober Teamor some other promising horror studio picks it up for its next game. Or maybe give it to the team behindHello Kitty Island Adventureand really throw a curveball at people looking for a relaxing time by suddenly flashing to a screen where Chococat’s head is on backwards.





