Most fights start off with dispels. If someone doesn't sufficiently pad themselves with junk buffs, and you manage to dispel their important buffs, it becomes a huge advantage (or disadvantage if you're the one who lost your sow). Pumice stones give even non-casting classes the ability to dispel, but they're not instant, so you generally use them on someone that you get the jump on.
Don't expect people to stand still like mobs. Some people will gate out, some people will run, some will plug (basically killing their internet connection to avoid a death), and some will fight back. You never know what you're going to get, which is part of the excitement vs a completely scripted encounter.
There are some tricks that you'll see people use in pvp that you'll rarely see in pve. Jousting, corner casting, people using guards to their advantage, the list goes on. I thought of typing up a quick guide for people switching from blue just so they're not completely blindsided, but laziness always wins out.
Always assume that people will use every advantage they can. Some people have some vague notion of "honorable" fights, but those rules only exist in your own head, so don't expect people to follow them. The other day someone killed me after the mob I was fighting beat me to about 20% health. That's not something to complain about, they were just being smart.
See you out there
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