When you complete a quest you get a quest point, when an amount of quest points are achieved you can chance to a new mage rank
D Rank to C Rank = 5 Quests
C Rank to B Rank = 6 Quests
B Rank to A Rank = 7 Quests
A Rank to S Rank = 15 Quests
S Rank to SS Rank = 35 Quests
For all quest completed you will get account points, from this account points you can buy new character slots
D Rank - 1p,
C rank - 2p,
B Rank - 3.5,
A Rank - 5 P
S Rank - 7.5 P
SS Rank - 10.5 P