An Evoker can turn whole armies to molten slag, armed with nothing but a bathrobe and a harsh word. Unmatched in the field of magical power, they harness their Focus through complex rituals and mystical tattoos covering their bodies.
Evokers have the biggest single-burst damage in the game, located in one of their invocations, Overload.
Drawbacks
An Evoker who doesn't wear Light or Unarmored-class torso armor loses out on the use of their neat passive abilities.
No physical damage capability without a secondary class, making enemies with high RES or spell-reflection abilities a real problem.
Silence makes you useless if you don't have an option to counter it.
Evokers can be squishy and easily killable.
No matter how much you like turning people to molten slag in a bathrobe, the lack of equipment will cripple you more than if you were using Pure Power.
FP costs. You're gonna be struggling in that department.