The Guild Wars community is deeply polarized around PvP and PvE. Very few players dedicate a lot of energy to both, and fewer yet are successful at both. One reason is the difficulty in learning PvP when you're accustomed to PvE; the two sides of the game are designed differently. There's a huge hurdle here. Someone who has learned the game while leveling up to 20 has a lot to unlearn to have a chance at playing PvP at a high level. It causes a lot of players to miss out on the beautiful PvP system which, to my mind, is the shining feature of the game.
In this article I'll try to point out the most common mistakes PvE players make when trying PvP, as well as basic concepts a lot of beginner players don't immediately grasp. Hopefully this article will help experienced PvPers as well, in that they can post a link to it when they don't want to explain why Mending isn't a good way to stay alive.
First, some concepts to internalize if you hope to succeed in competition:
1) Versatility in teams, not in characters
In PvE you can't always count on your allies to cover your back, so it's understandable when you bring some defensive skills even if you are a damage dealer. In PvP, if you can't count on your teammates, then you can't hope to win at all. Make sure your character focuses on what it's best at, rather than spreading too thin.
If you are a Monk, don't cast Fire Magic spells. You have the Divine Favor primary attribute, so your healing spells are inherently more effective than anyone else's. Use your Energy for that and leave the Fire Magic to the Elementalists.
The exception is the split character. If you're running a character designed to split off on its own to run flags or kill NPCs in the enemy base, it is perfectly fine to bring several self-sustaining skills.
2) There is no tanking against players
In the same vein, don't run Shield Stance or Dolyak Signet on your Warrior. A PvP Warrior needs to focus on dealing damage, because opponents merely ignore defensive Warriors and go after softer targets. If you do enough damage, you accomplish two goals: 1) you force the opposition to pay attention to you, drawing fire away from weaker allies; and, 2) you kill enemies before they kill your allies. A Healing Signet or Signet of Malice to lighten the load of your Monks isn't a bad thing, but don't try to be a tank. Alone against several skilled opponents, you won't accomplish anything. As a Warrior, your ability to keep your teammates from dying is very limited. Focus on killing opponents before your teammates die and let Monks, Paragons, and Ritualists handle defense.
3) Resurrecting isn't a Monk job
Though most resurrection skills are Monk skills, they're not best used on a Monk. If your Monk begins to cast something that takes six seconds to complete, the enemy team has a huge window to bring all of their damage to bear while one of your Monks is rendered completely useless. Expect a good team to get at least one kill in such a window. It is better to bring several Resurrection Signets on damage dealers and one rechargeable resurrection skill ("hard rez") on a midline character like an Elementalist or Paragon.
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