Why do certain skins become a line
Some skin lines like bloodmoon and battlecast are kinda cool. I'm glad we get pool party and christmas skins every year. What I'd like to know is how come other one-off skins don't get a line of there own? I mean there are a few skins that only one champ has I'd love to see added to others. As a random example, every sword user either gets a chosen skin or a frostblade skin (WTB frostblade Leona Iron Stylus please). Maybe have a skin line for every champ in a specific role: IE a diamond line for the tanks.
I can think of more than a few examples of skins that only one champ has that'd make a great line.