Not all Servants gain equal stats upon leveling up. Each Servant has their own Growth Curve, which is what defines how many stats they get every time they level up. Growth curve trends are viewed over the entire leveling process, from level 1 to max level after ascending all 4 times.
Grailing follows a special curve which advances independently from the servant's own growth curve. 5 grailings from lv90 to lv100 grant roughly 1000 HP&Atk varying from each servant.
- Linear: Gain the same amount of stats every time.
- S: Gain few stats per level at the beginning and end, but a lot in the middle.
- Reverse S: Gain a lot of stats per level at the beginning and end, but very few in the middle.
- Semi S: Like S, but not as good at the middle, and not as bad at the beginning and end.
- Semi Reverse S: Like Reverse S, but not as good at the beginning and end, and not as bad in the middle.