Experience values of monsters

The following is a spoiler for experience values of monsters for vanilla Nethack 3.4.0. Insert obvious spoiler warning here, despite the fact that this is a spoiler.

(Spoiler version 0.02) last changed: 2002-09-05 [minor changes])

Corrections and suggestions are always appreciated. ^_^;;
-Hojita Discordia

1: Definitions

2: Assumptions

3: Experience Table

4: Rodney Table

1: Definitions

Level: The experience level of the monster. This influences a few things. For one, the square of the experience level is directly related to the monster experience. The higher level a monster is, the more likely it is to be generated with an offensive item. Also, the higher an experience level, the more likely that monster will be able to hit you (one experience level negates one point of your AC). The higher a level a monster is, the more spellcasting ability it has as well as the more ability it has to resist magical effects.
Difficulty: The relative difficulty of the monster. In general, so long as monsters haven't been extincted, Nethack will create monsters of difficulty at minimum one sixth of the dungeon level rounded down and at maximum the average of the dungeon level and your experience level rounded up. If all the monsters in that range are extinct or genocided, then Nethack won't randomly create any monsters on that given dungeon level.
Dungeon Level: The current level in the dungeon, so long as you don't have the amulet or are in the end game. If you have the amulet then the current level is considered to be the deepest level you have reached (the sanctum). If you are in the end game, then the current level is considered to be the depth of the sanctum level plus half your experience level.
XP: The experience points you get for killing a monster, based on the assumptions given below. Extra formulas are given to calculate the more/fewer experience points if the assumptions are not correct.

2: Assumptions:

Since while playing the game, experience is somewhat dynamic based on a few factors, there are a few assumptions made to calculate "base" experience points for any given monster.

Monsters are naked.
If a monster is wearing armor, its AC will be lower and you will get more experience: [not cumulative]

Final AC: Bonus experience
2: 5 more
1: 6 more
0: 7 more
-i: (7+i)*2 more
You are not amphibious.
If you are, you don't get the +1000 points for eels, kraken, etc.
Dungeon level is not taken into account.
The dungeon depth is considered to be the dungeon level you are on. See above for what an accurate calculate of dungeon level is. If a monster has a level greater than the dungeon depth, then it is generated with one less experience level. If it has fewer levels than the depth, then it is generated with one more experience level for every five its level is fewer. The change in experience points for a monster of level n that is now a monster of level n+1 is 2n+1 more experience points. If it is a monster of level n-1, it loses 2n+1 experience points. If that level is now above 8, then it gets an extra 50. If it is now less than or equal to 8, subtract 50.
Your level is not taken into account.
If a monster has a level less than yours, then increase its level by 25% (rounded down) and follow the same rules as above to find the change in experience.
Monster hasn't been drained or has drunk non-cursed potions of gain level.
See above.

This was all created by severely hacking the relevant functions in makemon.c and exper.c to get a meaningful experience value. I wanted to write a general utility program that would use the Nethack source and would work for any and all versions, but due to the assumptions that had to be made, I didn't get one finished. Maybe if I just re-defined all functions that I wanted to hard code it would work. It'd be an ugly hack all the same.

4: Rodney Table

Every time you kill the Wizard of Yendor, he comes back stronger. In game terms, it means that the level he is created at increases one for every time you have killed him up to a max of 49. Since he starts at 30, on the 20th time you kill him and every time after that he will "only" give you 3,153 experience.

Previous times killed -- amount of experience

0  -- 1386 experience
1  -- 1461 experience
2  -- 1538 experience
3  -- 1617 experience
4  -- 1698 experience
5  -- 1781 experience
6  -- 1866 experience
7  -- 1953 experience
8  -- 2042 experience
9  -- 2133 experience
10 -- 2226 experience
11 -- 2321 experience
12 -- 2418 experience
13 -- 2517 experience
14 -- 2618 experience
15 -- 2721 experience
16 -- 2826 experience
17 -- 2933 experience
18 -- 3042 experience
19 -- 3153 experience /* maxes out */
20+ -- 3153 experience

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Experience values of monsters

Table of Contents

1: Definitions

2: Assumptions:

3: Experience Table

4: Rodney Table