Top three Damage Dealers in the game are Wizard, Cleric, and Archer. Wizard and Cleric both do massive magic-based ranged damage, while Archer does high physical ranged damage. Cleric has a skill that adds some physical damage based off their magic attack, while Archer has skills that add magical damage based on their physical attack. (Wizard does only Magic, pure and simple.)
Wizard is my personal favorite out of all the classes. Barbarian then Blademaster make up my top three. Cleric, then Archer and Venomancer my bottom three.
I like Wizard best because of the diverse skills. You get 3 elements, which you can use to take advantage of the weakness in Water, Fire, and Metal mobs - doing even MORE damage. Clerics, meanwhile, only do Metal damage which only gives them an advantage over one type of mob. The channel and casting times for Wizard are the longest in the game, but it evens out very well with the damage they deal. In short-term battles (supposedly under 15 seconds) a Wizard will out-damage anything its own level. So they say. Archer is supposed to be able to out-damage a Wizard in longer time frames. I haven't seen the math proof for either claim though ;)
Wizard gets you to think on your toes, and is more engaging (for me) than any other class. Most PvE server wizards are Arcane Robes, which means they need to Kite a bit more (string the mob at a distance while maintaining attacks), so that they don't take as many physical hits to their small HP bars. Archers in early levels are also instructed to Kite some because they get small HP bars too, but they get knockback skills that keep mobs at a distance later. PvP Wizards tend to favor Light Armor, which gives much more physical protection, while still giving decent magical protection against magic classes and mobs.
Cleric is similar to wizard, but with a variety of healing skills (Wiz has one healing spell) in addition to attack skills. There are far, far, far more Clerics than Wizards. And a cleric will be followed by cries of "Heal Pl0x" and "res plz" wherever they go, taken for granted, and generally have their own personal interests trampled upon by people whose only concern is themselves. They tend to forget that clerics arent' their personal slaves :p That is why I like Wizard better. Same high damage, less servitude. (And this from a woman who is usually spending her time helping others. There can be too much helping...) Clerics are always in demand, while the demand for Wizards comes later in the game when bosses are Magical (Wizards tank them well), and TWs need great DD's to take out the catapullers - a Wizard specialty. In a pinch a wizard can act as backup and heal a squadmate on quests, but this isn't recommended for dungeons as the skill is too slow. Clerics are and will always be the best dungeon healers ^x^ More skills that heal, with less casting time, means they can heal more often and use the healing on a greater number of people.
As for Archer... I'll admit, the class has its fun points. But it's also rather frustrating, especially after playing Wizard (awesome PvE DD) and Barbarian (poor attack power but great PvE defense, and high dex makes grinding easy). Things go a bit slower than it did for me on Cleric or Wizard, with the mobs getting to my Archer more easily than either of those two (My archer is full dex so I have her with top damage for her level, too). But the option to fly out of the way when you're in trouble, from any level, is nice to have if you need it. Archer has no healing skill of their own. And eats pots like MAD.
Sorry I'm not more constructive on Cleric and Archer but they don't appeal to me personally to much... Wiz and Barb FTW ^x^
PS: Blademaster is fun too. It's a melee class, and probably fourth on the list for DD if you don't count a Veno's pet. not sure how it compares to those. But the wide skill variety and animations make it very enjoyable to play. Not to mention the huge weapons selection, tailor those to your personal visual tastes or the skill path you want to choose, either way, very cool. They're more of a Secondary Tank/DD than anything - called upon if you can't find a Barb to tank a dungeon a lot.
Wizards are the least common class in the game, making the demand for them high later on. Clerics are probably second most common, after Venomancers which I could swear make up 30-40% of the server population sometimes. Blademasters and Barbarians are also uncommon in certain levels. Lots of Barbs in the starter towns, very few later on.
Leader of Howl on Harshlands (Recruiting.)
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