I will show below in screenshots, what is my strategy to kill it. I don't suggest its the best, but it has a 90%+ chance to succeed.
Typical combat team is 2 Boars, Golem, plus one more fighter (we don't care which one)
Hero is wearing a kdel/knod armor. Using the keel/dom is very risky, since one of the bosses hits at slash
Step 1:
4th companion tanks one Boar
The other three hit the Insect while hero hits middle mob.
Usually Golem hits 60s-70s at the insect and the Boars finish it off. If this happens, then the next steps are very easy. But Golem misses a few times and then we need one second round with Hero tanking the Boar. But after either 1 or 2 rounds, the insect is down and we go to step 2
Step 2:
Hero needs to tank the Boar for 1-2 rounds, while the 3 companions hit the Powerclaws which has a 70% shield.
The second round usually the Boars kill Powerclaws before it has a chance to hit you, so you normally get hit once once from it.
In general you may get hit in total a max total of 5 times from all the mobs until the end of the combat, which is not likely to mutilate you. On my lucky tries, I usually get hit only 3 times total.
Step 3 :
Golem tanks Boar
2 Boars and hero hit the last companion
If you are after Urban levelling, you might consider using 2-3 rounds to hit only with Hero, while the Big mob kills Golem and Boars one by one. After 2 rounds anyway, he loses Vigor and cannot 1-hit the Boars. And usually he doesn't 1-hit Golem even with Vigor on.
That's my tactics. Nothing fancy, just a quick guide for anyone interested.
The boss drops:
azulio planks, nocturnal leather, krya plates all of them a bit rare something like 10% each
tickpick stings (100%)
the rest are complete crap
