This is the lightning version of Fire Blast. It hits only once, but hits rather hard.Like Fire Blast, Lightning Ball's damage is computed recursively. clvl and slvl influence its damage.
Base Damage = rand(80) + rand(32 * clvl) + clvl + 20
For each level in Ball Lightning, multiply it by 17/16. Let's say my Assassin is clvl 8 and has 2 levels in Ball Lightning:
(Note: Assume our two random numbers are 48 and 173)
Base Damage = 48 + 173 + 8 + 20 = 221 + 28 = 249
Level 1: Base Damage = 249 * (17/16) = 264.5625
Level 2: Base Damage = 264.5625 * (17/16) = 281.09765625 (let's round it)
Final Damage = 281
Unlike Fire Blast, Ball Lightning hits a single time and does not inflict splash damage. Thus, it hits harder, but will only strike one enemy.
This information was updated using the written guide for versión 1.205d created by Daniel Campbell/sbx.