After spending almost the entire night hunting on the Wolves, and in spite of always non-stop blasting into them with a MIDA and legendary-level specials and heavies with a lvl-31 character, every time I've only just been able to start on the final major boss and the Wolfies get bored and leave. It definitely looks like it's only possible if (a) non-solo'ing, or (b) lvl 32? Is that the experience of other people?