Experience and Level Scale
about 1.5 growth
Level 1: 0 exp
Level 2: 50 exp
Level 3: 75 exp
Level 4: 112 exp
Level 5: 168 exp
Level 6: 253 exp
Level 7: 379 exp
level 8: 569 exp
level 9: 854 exp
level 10: 1281 exp
level 11: 1922 exp
level 12: 2883 exp
level 13: 4324 exp
level 14: 6487 exp
level 15: 9730 exp
And so on. There is no hard cap, but it just becomes silly after awhile how many monsters you'd have to kill to get another level.
How it's shown to the player
In their paper doll screen on the inventory, they see a number. This number is how much experience they still need to get the next level. So let's say they JUST got level 11. The number would then read 2883. If they then got 800 experience and looked again it would say 2083.
How it relates to the dungeon levels
We want players to kill an average of 30 monsters per level.
Dungeon levels should spawn with enough monsters to basically get you a full level, at your expected level.
Level 1 you're expected to be level 0, so the dungeon's core spawned monsters will yield at least 20 exp.
At dungeon level 6 you're expected to be level 7 (i believe) so it should yield around 150 experience.
Using this formula we can determine how many monsters should initally spawn.
Also there are extra monsters which the player can use to grind a little bit with if he is behind, or to get a bit ahead with.
So for level 1, you are about level 1 and you need 20 exp to get to level 2.
Bandit = 2 exp
Rat = 1 exp
For level 6, you should be about level 9. So you need 512 exp to get to level 10. So there should be about that much exp on the level when it is created.
At all odd levels, you pick a skill - this includes level 1.