Powers
Powers, also called Skills, or Spells, are the special actions a player can do to help in combat. A player casts a power, which requires a certain amount of mana, and takes a set amount of time (casting time, 0-6 seconds). After being cast, each power has a certain cooldown time (5-240 seconds), during which the same power cannot be cast again.
Disciplines
Each basic class in the game has 4 disciplines of powers, and each discipline contains 10 skills, increasing in power. A character starts off with just one powers in each discipline, and as a character levels up, he can add more powers to his repertoire. When the character chooses a subclass, he gains an additional 2 or disciplines of powers (or 3 for mages).
Power Types
There are 5 types of power: Instant, Constant, Activable, Aura and Passive.
Instant
See also: Instant Powers
Instant powers perform a single action immediately. Most often this is dealing damage to an enemy.
Constant
See also: Constant Powers
Constant powers perform a certain action that has an effect over time. This can be from a few seconds to as much as 5 minutes. Constant skills can also have an "Instant" component, eg a skill could deal some immediate damage to any enemy but also cause a negative effect to them for some amount of time.
Activable
See also: Activable Powers
Activable powers are similar to constant powers, but they can be deactivated early, thus cancelling the effects. They usually increase one attribute of a player but decrease another, giving the reason why they would want to cancel the spell.
Aura
See also: Aura Powers
Aura powers are similar to constant powers, but they are a special type which gives some benefit to all allies surrounding the caster. If an ally moves away from the caster, he will lose the benefit, but can regain it by moving close again.
Passive
See also: Passive Powers
Passive powers differ from the other types of power, in that they cannot be cast, (and therefore need no mana); simply having the powers increases a particular attribute for a character.