The original XP formula was designed before Ascension existed, so Level 20 was considered the "end game".
This is no longer the case. 10x Ascension + Level 20 is now the "end game" for a highly dedicated player.
Reducing XP requirements also makes the game more friendly to new and casual players, who can then participate in Guild PvP.
The XP formula will be reduced with the next update and applied to all fighters retroactively.
1 500
2 1,000
3 2,000
4 4,000
5 8,000
6 14,000
7 22,000
8 32,000
9 44,000
10 58,000
11 74,000
12 92,000
13 112,000
14 134,000
15 158,000
16 184,000
17 212,000
18 242,000
19 274,000
20 308,000