I'm making a new RPG game that has loot, in fact a majority of the game is based around loot. It's going to have colored borders to denote the rarity of the loot as it's drawn. WoW uses Grey, White, Green, Blue, Purple, Orange and some others. GW2 uses Gray, Black, Blue, Green, Yellow, Orange, Pink, Purple. The colors don't match but you can see some distinct overlap. I'm wondering if those colors are important or intuitive to users understanding of the rarity or if they can be messed with? If they can be changed how do you determine what colors to put in what order? For instance, if I went with White, Blue, Green, Yellow, Red; would that be fine as long as I made it clear in other ways or would those colors be confusing?