There has been a lot of PvP lately, and there are three commands I'd like to bring to everyone's attention in case they're somehow unknown:
/c hostile all
/c hostile [fullname]
/c setally [partialname]
/c setally --nearby
If you're attacking someone or even planning on maybe doing so, setting the people around you as allies so that you can easily set the rest of the server to hostile is a good idea. Or just hostile any enemies you have that you would attack on sight before you leave Sanctuary/Lower. Bards, summoners, and evocation specialists in particular struggle against people with big weapons that aren't hostile who can just right click and attack someone who they're blue to.
Please hostile your enemies if you're planning to attack them.
PVP player tool is also super helpful for this. Would recommend using it. Also changes your subdual mode if you target yourself with it. Very nifty.
I recommend putting /c setally --nearby and /c hostile all somewhere on your hotbars. It makes huge group PVPs really easy.
It really is deeply frustrating fighting a group of foes who haven't all set hostile before ganking. Please set hostile guys.