Yes, there is a formula. Both Spell Power and Magicka affect how much damage a skill that magicka uses. The same goes for stamina.
Before you can use the formula, you need a few pieces of information.
- You're base Magicka with no attributes points spent, no armor, no buffs, no CP spent, no nothing. If you're VR 14 it's 7,958.
- The skill's base damage with nothing spent/equiped.
- Note: if you need the two above numbers, you can hop on to PTS and figure them out for VR14 pretty easy. For skills just make a new VR14 character and don't equip or spend anything and equip the skills.
Once you know you're base stuff, you can calculate how much the skill would do with different levels of Magicka and Spell Power.
You also need to factor in any Passive Increases. These would be from armor and CP buffs.
*Note: This calculates within a range of +3% to -9% due to rounding error. It's not perfect but it gets you really close.
{[Skill Base Dmg * 0.0001260819076114 * (Buffed Magicka - Base Magicka)] + (Buffed Spell Power * Skill Based Damage * 0.001306135) + Skill Base Damage} * (1 + Passive Increases)
The formula works for Stamina as well. Just swap Magicka and Spell Power for Stamina and Weapon Power.
Edit: This formula doesn't work for Ultimates.
Thank you for the answers! Unfortunately I do not have the PTS, but if my understanding is correct the contribution of both magicka and spellpower to DPS is linear - no diminishing returns (especially since there are no soft caps anymore). This means that if additional 1 point of spell power is equivalent to roughly 10 points of magicka, given the current set bonuses a spellpower bonus will always be better than a magicka bonus. Although I would need to look at all the passives and buffs to take that into account, considering that any additional spell power or magicka that I get will be multiplied accordingly. Is that correct, or am I missing something? Thanks again!
Also in the formula:
{[Skill Base Dmg * 0.0001260819076114 * (Buffed Magicka - Base Magicka)] + (Buffed Spell Power * Skill Based Damage * 0.001306135) + Skill Base Damage} * (1 + Passive Increases)
What exactly is base magicka? Is that attribute points + level based magicka?
Passive increases is cp only or passive skills or what?
I'm really confused on this one. It appears that base magicka is completely removed from the equation...but I know that as i level my magicka pool gets larger and this adds to spell damage.....unless the skill base damage is taking this increase into consideration automatically....
Can you elaborate on the variables in the equation ?
It looks like it might be able to be simplified such that an end user could input their current spell power and magicka and their proposed new spell power and magicka and an output of increase/decrease in the damage could be calculated...which could then be directly multiplied against the current spell damage for the new damage value for a specific skill?
So if it worked a user would need:
Current Magicka
Current Spell Power
New Magicka
New spell power
And these could tell you if it made you stronger
Then for a specific skill the current damage value could be entered to produce the new damage value with the rest of the work done behind the scenes in a simple interface where a user can enter 4 required values and up to 10 optional values (5 active skills on two bars) to know the full change before buying/crafting the gear....dunno if this is useful?
@Feynn Op
Here OP provided the above numbers are corrcect from the other posters you can simply put your numbers into the calculator for an answer.
http://asolutionaday.com/general/magicka-v-spellpower-calculator-tesotu/