Im on my fourth run through of darkrime delves and on less than 150 kills, so I decided to keep an eye on my kill counter, I got to 142 kills, then I killed a veteran, a skelk and something else that got in my way all at the same time, after killing those 3 I was then on 143 kills. the counter obviously isn't working as intented unless im missing something. edit: got less than 15 counted kills in the whole instance.