And some more..

1. If you slash a pig many times, it will kill you. (LOZ: Wind Waker)
2. If you're moving around in a barrel, no one will notice you.
3. Sheep are fodder for dragons. (Spyro)
4. When your controller vibrates, shit's about to go down.
5. The main character is either a badass or an unbelievably nice guy.
6. There's always a damsel in distress.
7. 0.00000001% of characters are bald.
8. If the character is bald, they wear sunglasses.
9. If the character is bald, they are accompanied by a comic relief character. (Final Fantasy)
10. When you wake up from sleep, the world has ended.
11. No matter what parallel universe you're in, your hero clothes always have to be green (and serve no power whatsoever).
12. A fairy can either say 'hey', 'listen' or 'what's up' and you usually want them to shut up.
13. Peahats are NOT giant pineapples. (I had to learn that the hard way.)
14. A bad guy has many forms.
15. There's always an androgynous character.
16. The uncoolest and least popular guy in school is always the hero.
17. It's not always 'just as planned'.
18. Never trust a shinigami.
19. British characters always have an exaggerated accent.
20. When the sky darkens and clouds appear, you're screwed.