Video game worlds are built to be explored. From Monster Hunter to Assassin's Creed to the cutesy bricks of Lego Harry Potter, you're encouraged to have a good old sniff around the place, collecting artefacts, breaking down walls, annoying NPCs, and generally being a nosy little bugger.
Hell, even kart racers tempt you to go off-road in search of hidden shortcuts, and this constant loop of exploration and discovery is a rush that only gaming can really provide. Well, and going outside. But we all know which is better.
However, there are some places - cue the sinister music - that you and your video game avatar were never meant to go.
Riddler trophies, underground tombs, intel items: games are littered with secrets that the developers meant for you to find all along, but a lot also contain off-limits things, stuff that was supposed to be sealed away and never found by anyone.
You weren't really supposed to find these secrets, but come on, unbreachable barriers and layers and layers of complex code are no match for a determined gamer with plenty of time on their hands.
10. The Developer Photo (The Witcher 3)
The Witcher 3 is one of the biggest games of all time, with dozens and dozens of side quests to complete, beasties to slay, and a robust campaign to get lost in. Even if you just want all the achievements or trophies, you're looking at well over 100 hours.
With so much content came a plethora of secrets to uncover, and while the majority of those were obviously supposed to be tracked down by players, this hidden photo in the Blood and Wine DLC does not fall into that category.
The image - a shot of the CD Projekt RED development team - can be found atop Mount Gorgon, an area that, through normal play, is located outside the boundaries of the map. But when players installed a camera mod and started exploring, they were able to search through areas that would otherwise be sealed off.
After moving the camera into the right position, you can even teleport Geralt to the top of the mountain and have a run around yourself. It's a beautiful sunny location, and the picture almost looks like a shrine dedicated to the blood, sweat and tears the team poured into the game.