After extensive testing with the ability, I have found several issues with killing spree, however before that I would first like to point out the wording in the tooltip:
“Step through the shadows from enemy to enemy within 10 yards, attacking an enemy every .5 secs with both weapons until 5 assaults are made, and increasing all damage done by 20% for the duration. Can hit the same target multiple times. Cannot hit invisible or stealthed targets.”
I would like to place emphasis on the “until 5 assaults are made” because as the AI is now, Killing Spree will often end after only making 1-4 assaults, the assaults that are missed result in the rogue standing still for that interval due to the nature of the AI.
Killing Spree in its current form works like this, upon activation all valid targets within 10 yards become possible targets for an assault. If any targets move into range, or if any of the targets move out of range or die, the list of targets that killing spree will attempt to assault will not change. It will attempt to make assaults on targets that are out of range (your range is always 10ft from the last assault) as well as targets that are dead, resulting in no assault being made.
A really good example of this is the Sartharion Fight, Sartharion’s hit box is ridiculously huge, and as long as you are on his side of the platform, the edge of his hitbox is usually within 10 ft of you. For most of the fight he is tanked off to the side by himself, meaning that if you use killing spree and it selects him for an assault, you will teleport directly to the center of him, and if that’s more than 10 ft from where you activated killingspree, Sarth is the only available target left in range, and lets say you had a drake, 2 elementals and sarth all in range… each assault after the first one to land on sarth would have a 3/4 chance to pick a target out of range and do nothing.
This behavior makes killing spree very difficult to use on any fight with more than 1 target, which doesn’t really make for much of a killing spree, at the very least we should be able to get 5 assaults every time.