Energy Orb

Most likely, this is based on spawn order, and would be quite the fireworks show with higher mob hits..

Here's how I think it works, I'm 90% sure it does this. The Captain that received the second hit was in motion, so I moved it to the place it was when I activated Energy Orb, simply to explain it better.

 Spoiler

This is the area I can hit with Energy Orb. As you can see, the damaged Kru is in the area, it's also the nearest.


This is the area the Orb will hit after bouncing off the damaged Kru. The Captain is barely inside this range.


This is the path that the Orb draws (not the ball graphic). I assume this is the way it finds out which monsters it will damage.


After figuring out which monsters it will damage, the skill applies the highest damage to the nearest one to the player (Captain), then the 2nd nearest, etc.

This leads to misleading results when observing your own damage, and why noting two 4ks earlier was important to rule out it being a possible first orb striking in a different order.

Hilarious. "Oh damn! Second did 9k!!! What the hell!?"