Arcane energies are powerfully intoxicating and addictive. Therefore an Azerothian mage, to put it bluntly, is not unlike a drug user. Some may claim to use the powerful "drug" of arcane energy responsibly - "I can quit anytime I like" - and others may be deep in the throes of their addiction and could care less what anyone might think. But every mage on Azeroth must constantly fight the call of addiction and madness if they intend to harness arcane energy for their own purposes. Those mages who remain sane into old age are those of exceptionally strong will and self-control. And they are few and far between.
Mages can do whatever they like, of course, but it's nice to know what your group will be expecting! Your expected role is essentially "ranged DPS," a military slang for "ranged damage per second." Terms such as "DPS" reflect the military's endless quest to measure and quantify the art of killing.
Mages are expected to stay OUT of the line of fire and to attract as little attention to themselves as possible, while also dishing out massive damage. Yes, this is a contradiction in terms, and this is why there are very few stupid mages. It's a fine balancing act between making the most of your ability to hurt enemies and keeping said enemies from getting (rightfully) mad at you. Having a good warrior on your side can help - warriors are masters at pulling enemies off of "squishier" classes, but in the long run it is up to you. You must learn to time your strikes, use whatever tools of subtlety you can manage, and/or do so much damage so fast that nothing has the time to kill you. Each mage finds his own "tricks" that help him blend into groups without being a flashy liability.
A mage's armor rating and physical weapon damage are of virtually no importance, since ideally mages will never even get close to their opponents. Instead, mages should seek out enchanted robes, jewelry, trinkets and ornamental weaponry that will enhance their Intellect first and foremost. Secondly one might consider Spirit, which boosts your ability to regenerate health and mana, and as a last resort, Agility can help you evade close-range blows, and Stamina can help you survive the ones that land. Look for items marked with the sign of the Owl (Intellect and Spirit), Eagle (Intellect and Stamina), Whale (Spirit and Stamina) or Falcon (Intellect and Agility).
ALOOF, ARROGANT, AWKWARD, COLD, CONTROLLING, CURIOUS, ECCENTRIC, ERUDITE, IMPETUOUS, INDEPENDENT, INSATIABLE, INTELLECTUAL, INQUISITIVE, PASSIONATE, POWER-MAD, QUIET, STUDIOUS, WHIMSICAL
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