I posted about this topic last week and received no response from a mod.
Edited by Caspur on August 29, 2014 1:38PM
Basically, the problem is, when fight 2 or more NPC enemies and I kill the first NPC and then I use invisibility, I deal 0(zero) damage to the second NPC enemy. This happens in about half of my fights that I use the invisibility skill.
I figured out why this is happening and figured I'd post in case anyone else runs into this problem.
When the first NPC dies and I go into invisibility the second NPC will sometimes stop fighting and put his weapon away. If you attack the NPC while he is sheathing his/her weapon and you are invisible your hit will do no damage. You will also lose Magicka/Stamina or your Ultimate Ability points if you attack while this is happening.
I've also noticed that sometimes (rarely) if you are engaged in a fight and use invisibility the NPC or NPCs will stop the fight and regain all their HP.
Note: These are all solo fights this happens in. If you are in a group this probably will not happen because the enemy will agro the next player.
A place where everything and nothing exists, this is my playground.