at low levels, you wont have problems with any tppking (aka triggers, though i think its possible to do it manually as well) Where they spam the killing skill (in your friends case, BH, its also commonly a bone spirit) then go to town and hostile before the skill hits a now hostile party member, killing them (thats the idea anyways, its possible to survive them, though hard)
At low levels, just play smart, learn to watch for pkers, signs:
Appropriate levels:
pkers will very often (95% of the time) use some +max jewels for the damage boost, so watch for the level reqs on those jewels, usually level 18 is what to watch out for, though level 9's are also common pks.
Common levels for pkers:
9, 12, 18, 21, 24. (9=wrath jewels, 12=charge and other new skills, 18=carnage jewels, 21=sharp/fine charms, 24=bonesnap, only watch for paladins at 24)
Not to say pkers will only be these levels, but most are, if they ARE an exception, it will probably be between 12 and 18.
Watch for people in the wrong place for their level, if there is a level 18 in town in your sewer game, be wary, good exp stops before you hit 18 in the sewers, so why is an 18 in the game? Could be looking to pk.
Many pkers are paladins, because its an easy build, lots of people new to pking (or lazy, in search of an easy build) will make a charge-a-din, so be espically wary of paladins.
Look at equipment (no, not maphack) look people wearing masks or crowns (not many act2 pvmers wear them, but pkers do quite often because they can easily hae 3 sockets, which means 3 rubies or max jewels.
Look for red armor, pvmers will occasionally wear it, but a lot of folks wearing it are twinked out, and a twinked out guy in a sewer run often means pk.
Watch for 2 hand mauls at level 24+, likely a bonesnap.
Watch for any gear which most pvmers at that level are NOT yet using, for example, a crown shield, learn what it looks like, they dont often drop in act2, yet a 1 hand pker quite quite possibly wear it, learn what items look like what and if something seems out of place, check it out.
Most of all, just be heads up, if someone is not there to run the sewers, or arcane, or tombs or whatever it may be, then if you pay attention, you will likely pick up on this. If someone is standing on the waypoint in town, be careful, they might be waiting to ambush the party as it goes through, just keep heads up and you should be fine.
Dont hang around entrances to levels/wp's, if someone is going to hunt you, they are obviously going to come into that level from somewhere, put distance between that somewhere and your character, give yourself reaction time.
If someone hostiles you, either tp to town if you have a hotkey set, or save and exit, dont keep going, the pk usually will come looking, hoping someone will do just that.
That said, dont be paranoid, most people are NOT pkers, just a few are (i mean online in games, a lot of people here are, me included) so dont go being nasty and avoiding every level 18 paladin you see
I think it is NOT worth being overly paranoid, some people play all solo games to ensure they wont be pked, but myself, I would rather get pked than play alone all the time (or just be heads up, and play public games AND never get pked)
Good luck and welcome to hardcore!
-Matt
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