In Super Mario Bros. in level 2-1 you could go right through a wall via a glitch. Doing so would bring you to a warp zone. On the pipes it says -, 1, 2. Wait, -? Entering this pipe brings you to the famous "Minus World"(Actually its world 36) Its practicaly a water level that never ends, but by again glitching through a wall you can complete the level. Then you will go through other warped levels of the game.
9.Banjo Kazooie/Tooie mystery eggs and ice key.
I love these games, but they are known to have quite the mysteries between the two. In the end of banjo kazooie, 2 mystery eggs and 1 ice key were shown as unlockables. But, nobody was able to find them. People started to question, what do they unlock? It was only an amount of time until people found in-game cheats to unlock both of the eggs and reveal 4 other unheard of eggs. You could view these eggs in a menu where you would switch out the game with banjo-tooie while N64 was still on. This would of unlocked a 2-player cooperative mode, a secret level and a extra multiplayer character, jinjo.
8. L is real 2401. Super Mario 64.
Go to the back courtyard with all the boos in it. Look verrrry closey to the eternal star, it says "L is real 2401. What does it mean? Nobody knows. The phrase also appeared in Orciana of time.
7.Missingno. Pokemon Emerald.
In this game, you actually have a chance to find missingno, but the chances are 100,000 to 1 (no lie) that makes you 12 times more likely to find a shiny. (1 to 8421) As in every game, missingno will destroy your file if you put it in your pc. It looks like a black circle with a white question mark in it. Missingno is also related to the bad egg.
6. Shyguy's mask.
Shyguy has always been that crafty and calm guy that may or may not be an enemy. But! Just what is behind that mask? WHAT!? Only in a couple games shyguy has shown his "face".