Help with skill detail (static orb)

[7t7t7t]

If u check skillz details in kok u can see somthing like that.

Static Orb spell


Class: Mage
51 skillpoints in Lightning
Mana Consumption: 160
Cooldown time: 5.3 seconds
Description: Launch a charged Lightning ball
Effect type: HP change
Power: -882

Anyone knows what means Power and the effect type?

U may think...effect type...hp change means simply it decreases the hp of the target. Uhm...ok but so why certain attack_skilz (example. 5 arrows) dont have it?

Then i assume Power can be the a standard/common dmg of that spell. Maybe not. But then why the -?
But then again why for example certain skilz like archost or the cs dont have it?
ANyone knows what these voices stands for?

[IsgurosBous]

Probably it's only for the mage skills because those are less (not?) ap based, e.g. arrow shower is just 5x 100% damage.

[7t7t7t]

uhm nop...other archer's skilz ( LR shot )for example have the same descrption as for static orb. But i think i almost got it.