You probably know this, but I will mention it here anyway: although Hydra is a pet cast, its caster's
+% Fire Skill Damage (from Fire Mastery and items equipped) and
-% Enemy Fire Resistance both apply.
Hydra is explained in greater detail on the following page:
https://www.theamazonbasin.com/wiki/index.php?title=HydraQuote (Mukhalif @ 19 Mar 2019 19:26)
If your aim is to maximise Hydra damage, just remember
synergy bonus and
Fire Skill Damage are applied separately (
multiplicatively):
Fire Bolt/Ball
+% Fire Damage =
3 · (
Fire Bolt.blvl +
Fire Ball.blvl)
Fire Mastery
+% Fire Skill Damage =
23 + (
7·
slvl)
where
Fire Ball.blvl denotes
base level of Fire Ball (skill points invested in Fire Ball) and
slvl denotes
skill level of Fire Mastery.
Hence it is a matter of maximising the
product of
two percentages:
(100 + 3 · (Fire Bolt.blvl + Fire Ball.blvl)) · (100 + 23 + (7·slvl) + X)where
X is the percentage sum of
Fire Skill Damage from items equipped.
One might be tempted to suggest adding points to Fire Mastery is
obviously better (since
7 >
3), but this is
not always true.
The proper allocation of the next skill point (hence the +1) is determined by which of these two products is greater:
(100 + 3 · (Fire Bolt.blvl + Fire Ball.blvl + 1)) · (100 + 23 + (7·slvl) + X)
vs
(100 + 3 · (Fire Bolt.blvl + Fire Ball.blvl))· (100 + 23 + (7·(slvl+1)) + X)or, equivalently, which of these two fractions is greater:
(100 + 3 · (Fire Bolt.blvl + Fire Ball.blvl + 1)) / (100 + 3 · (Fire Bolt.blvl + Fire Ball.blvl))
vs
(100 + 23 + (7·(slvl+1)) + X) / (100 + 23 + (7·slvl) + X)ExampleLet us consider your current Fire Spells skill distribution as depicted on the above image (taking
X =
0):
(100 + 3 · (1 + 1)) · (100 + 23 + (7·9) + 0) = 106 · 186 = 19 716 (~ +97.16% damage)[1] Next skill point in Fire Ball or Fire Mastery; we choose whichever yields the greater Hydra damage:
109 · 186 = 20 274 (~ +102.74% damage)
vs
106 · 193 = 20 458 (~ +104.58% damage)or comparing fractions:
109/
106 (1.0283...)
< 193/
186 (1.0376...). Fire Mastery
is the better option.
[2] Next skill point in Fire Ball or Fire Mastery:
109 · 193 = 21 037 (~ +110.37% damage)
vs
106 · 200 = 21 200 (~ +112.00% damage)or comparing fractions:
109/
106 (1.0283...)
< 200/
193 (1.0362...). Fire Mastery is
still better.
.
.
.
... the trend continues. Notice how the gap narrows with each skill point invested. Eventually:
.
.
.
[10] Next skill point in Fire Ball or Fire Mastery:
109 · 249 = 27 141 (~ +171.41% damage)
vs
106 · 256 = 27 136 (~ +171.36% damage)or comparing fractions:
109/
106 (1.0283...)
> 256/
249 (1.0281...). Fire Ball wins.