In case anyone wants to know how it works, it's in healmagic.cpp.
You take base + stat bonus + class modification. They're divided into the three boxes below; just add them together.
All numbers round down.
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Base for vigor is 1d8 (1 eight-sided dice). For mend it's 2d7.
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Stat bonus depends on class.
For clerics and paladins, it's solely based on piety.
So 21 piety = +3 piety bonus.
For druid, it's the higher number between intelligence
and constitution.
For vamp, mage, and bard, it's the higher number between
intelligence and piety.
For all other classes, use constitution bonus.
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Class modifications are trickier.
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CLERICS
VIGOR:
mod = level / 2 + rand(1, 1 + level / 2)
So a level 16 cleric would get a base vigor modification of
[8 + rand(1,9)], or a range of 9-17.
MEND-WOUNDS: In addition to the vigor mod, you get: [level / 2].
Ares: heal at half level
Ceris: random bonus between 1 to 4
Gradius: modification gets cut to 3/4
Kamira: heal at 3/4 level
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PALADINS
VIGOR: mod = level / 3 + rand(1, 1 + level / 4)
MEND-WOUNDS: mod = level / 2 + rand(1, 1 + level / 3)
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OTHER CLASSES: mods are same for both vigor and mend
Deathknight: mod = level / 4 + rand(1, 1 + level / 4)
Druid: mod = level / 4 + rand(1, 1 + level / 5)
Monk, ranger, bard, vampire: mod = random between 1 and 6
Others: No class mod bonus
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So what does this mean?
Just add the three values together.
For a level 22 Gradius cleric, 25 piety (+4 bonus), mend:
2d7 + 4 + 0.75[11 + rand(1,12) + 11]
Min: 23
Max: 43
For a level 16 fighter, 25 constitution (+4 bonus), vigor:
1d8 + 4 + 0
Min: 5
Max: 12
What's the top vig in the game?
Level 30 Ceris cleric, mend-wounds.
2d7 + 5 + [15 + rand(1,16) + 15 + rand(1,4)]
Min: 39
Max: 69
Theoretically, that can be as much as 75 in a magic+ room.
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Order of healers (best first, same # = ties)
-- Improve based on level --
1) Ceris Cleric
2) Enoch and Aramon Clerics
3) Gradius and Kamira Clerics
4) Enoch and Gradius Paladins
5) Ares Cleric and Deathknight
6) Druid
-- No improvement based on level --
7) Monk, ranger, bard, vampire
8) Mage, thief, assassin, rogue, fighter
9) Berserker (can only heal off scrolls, which gives penalty)
10) Lich (can't heal)