Exp rate change if i got level ?

[[PH]KEO(DEV)]

Hello can i ask
if someone know how to Change Exp rate if i got level 50 or other level.
Ex. i leveling from 1 - 50 then if i got level 50 already the exp got high. example 1 level per mob kill. so its easy to level 51-70
i see this on server i play on last 2010 or 11 i think so i think is possible.. so if someone know.. thank you

[Soont]