Power Sets in Champions Online are the categories powers fall into. However, they are not "classes" in the traditional sense, players are not limited to one power set. Silver Members may only choose Archetypes, which specify power choices as you level similar to classes, whereas Gold Members may create Freeform Archetypes with virtually any power combination. The system is not completely open, however there are very few restrictions. All characters must choose an Energy Builder, and the power selection is restricted by "tiers." In order to pick a power, you must meet the prerequisites for its tier, which is either a number of powers from that powerset, or a number of non-energy-building powers from any set. As such, by level 14, any power in a set can be chosen if the player stays within that set, by level 23 any power in the game can be chosen by a player.
Note: The advanced info on all powers is based on a level 40 character with only 5 in all stats (the default), no slotted passive abilities, and Guardian role, with rank 1 of all the powers.
Note: The four martial arts power sets share several powers. For more detail, see Martial Arts.
Note: The brick power sets share several powers. For more detail, see Brick.
Note: The four sorcery power sets share several powers (see Sorcery) and the two supernatural sets share several powers (see Supernatural).