PER CHAMPION, PER LEVEL
ServerRank, friends and champions are all per region. We play on yours.
How it is played
Queue
RolesPick two or more so the booster has a choice. ANY is fastest.
Champions
pick 2+Mastery is tracked for each champion separately, so this is a catalogue with a quantity rather than a single order: pick the level, say which champions, and the price is per champion. Mastery 7 is the one most people still ask for by name even though the scale now runs to 10.
Because it is grinding rather than playing. The higher levels want a lot of games on one champion at a decent grade, which is the kind of thing people stop enjoying around level 6. It also shows on your profile and in champion select, which is the other half of why it sells.