11. Smoking To Reveal Some Lasers
It's the sort of thing that would get marked down as a 'game-breaking bug' these days - where throughout the opening hour or so of the first MGS if you didn't dart off the beaten path and nab the Thermal Goggles, you were essentially left to the mercy of some invisible red lasers and a corridor ready to gas you to death if you tripped them. Some people figured out a way around this purely from having the cigarettes equipped in Snake's mush at all times (smoking was way cooler in the 90s), but the rest of us had a few trips through the "Snaaaaake"-filled Game Over screens before realising the cigarette smoke could actually show you what to avoid the whole time.