As a mage, unless you are going 1v1, you should hang out in the back, stun and attack the enemies from a distance and heal/replentish mana as needed with a teammate between you and the enemy at almost all times when possible. You should also be one of the last in your team to die in a big fight as your role in the team is partially that of support and you are not doing this if you die early. You are doing you and your team a disservice if you try to be too much of a hero. Although I consider myself as that of a supportive role and have a defensive build as a mage, I still usually have a large number of my teams kills with this strategy, if not sometimes the most. Some of you may call it being a noob or a coward. Some of you may call me a kill stealer. But I think this is the best strategy for a mage in end game PvP. You will probably disagree, but this is just my opinion and you are free to disagree. Bottom line, if you want to be aggressive and run out in front be prapared to take a lot of damage. Perhaps, put up your shield, run to the enemy and do your thing, then try to get behind your teammates before your invulnerability wears out...