Variable
Under the Hood: Variable Effects
Powers based off the Variable effect are obviously very flexible, capable of duplicating a wide range of other effects. Responsibility for controlling Variable effects in the game is placed largely in the hands of both the Gamemaster and responsible players. To do otherwise would require weighing the effect down with numerous game-system limitations that would keep it from doing what it is supposed to do: create a wide range of effects.
Keep in mind a Variable effect is not supposed to be "any effect I want." That kind of unlimited power doesn't belong in the hands of player characters, and is better reserved as a plot device for NPCs. A Variable effect can be any effect within a given set of parameters, but it's up to you and the GM to define those parameters. The limits of power flexibility are deliberately set by Variable effects, the use of extra effort, and victory points.
Unfortunately many magic-wielding character in stories tend to have the ability to do anything they can think of, however this game won't give players a blank check to duplicate any effect in the game an unlimited number of times since that causes major game balance issues (and will likely slow the game down). Magic works well as a descriptor which can be applied to any power but there's no magic example power and you can't have a Variable effect of "anything magic" because that has no real limitation. However, generally speaking, magic users have certain abilities they use all the time (powers they have acquired with character points) and "stunts" they only do from time to time, essentially power stunts performed with extra effort (and possibly victory points).
Variable effects are better reserved for things where it is difficult to cost-out and define everything about a given power in advance. For example, the ability to shapechange into any animal could be an application of the Morph effect with a long list of Enhanced Trait options, but listing out every single possible animal form, one at a time, would be tedious to say the least, especially when a good number of those forms would be superfluous. A Variable effect, with the descriptor "animal forms" is easier to manage. The player can prebuild certain commonly used animal forms for use during play, but also has the option to new configurations that fit into the power's descriptors. See the Sample Powers section for some examples of Variable effects in practice.
In short, Variable effect is a "last resort" in power design, and the GM should treat it as such.
You can gain or use potentially any effect of the appropriate type and descriptor! A Variable effect provides you with a set of (rank x 5) character points you can allocate to different effects. This power has a minimum cost of 5/rank, flaws can't reduce it further. Take an action on your turn and choose where to allocate your Variable character points. It is a good idea to have a "menu" of commonly used options written down in advance to help speed up this process during play.
The effects you gain from your Variable effect are subject to the normal power level and series limits. So you cannot, for example, acquire Enhanced Trait as a Variable effect to improve a trait beyond its power level limit, or acquire effects or descriptors the Gamemaster has specifically banned from the series. The GM has final say as to whether or not a particular use of a Variable effect is appropriate and may veto your allocations, if necessary. You can't use Variable to decrease any of your normal traits (even if you are mimicing someone with negative abilities). Additionally you can't buy advantages that wouldn't make sense such as wealth.
You must also place descriptors on your Variable effect limiting its scope. For example, a Variable effect that mimics other's traits is limited to the traits its subject(s) possess; a Variable effect providing you with traits suitable to different shapes is limited by the form(s) you assume; a Variable effect providing adaptations is limited to the stimulus to which it adapts, and so forth. This descriptor does not reduce the effect's cost unless it's especially narrow or limiting, and the GM is the final arbiter of what constitutes a suitable descriptor and which descriptors are narrow enough to qualify for a Limited flaw.
The allocation of your Variable points is sustained by default, so if you stop maintaining your Variable effect for any reason, your allocated points "reset" to a "null" state: you lose any temporary traits and must take the action necessary to reallocate your Variable points again on your turn to regain them. Points in a Continuous Variable effect remain where you set them without maintenance, unless the Variable effect itself is countered or nullified. Variable cannot be permanent in duration by definition. However the effects gained by Variable may have permanent duration which would mean the the power gained can't be countered although Variable can still be countered or ended to end the effect gained. In this way a Continuous Variable can gain the effect of Permanent Immortality and in the event of death, powers gained by Variable will end as described in Gameplay Rules: Death with Immortality continuing by definition and Variable continuing because it is providing Immortality.
Extras
Faster Action: You can change the configuration of your effect faster. Gamemasters should exercise caution with Variable effects that can be reconfigured as a free action: they not only grant tremendous flexibility, they can also slow down game play as the player considers virtually infinite possibilities for each action using the Variable effect. Move Action: +1 cost per rank . Free Action: +2 cost per rank.
Affects Others: You can grant effects to someone else. The subject granted the use of the effect controls its configuration, if appropriate for its descriptors (although you retain the ability to withdraw use of the effect altogether whenever you wish). Affects Others Only: +0 cost per rank. Affects Others or yourself: +1 cost per rank.
Perception: Applied to a Ranged Affects Others Variable, this extra allows you to grant the benefits of the effect to any target you can accurately perceive. +1 cost per rank.
Ranged: A Variable effect with Affects Others may have the Ranged extra to improve the range at which you can grant the effect to another. This does not alter the ranges of the effect's various configurations. To do so, apply the Range modifier to the effect(s) within a particular configuration. +1 cost per rank.
Flaws
Limited: As noted in the description, a Variable effect must be limited by certain descriptors by default. To qualify for this flaw, the effect must be even more limited. This is highly situational and left to the Gamemaster's judgment. An example is a Variable effect only able to provide Enhanced Skills; in most settings, this is Limited. However, in settings where powers are rare and most characters rely on skills, it might not be. Conversely, a Variable effect prohibited from providing Enhanced Skills, but able to provide a wide range of other effects, isn't particularly Limited, just defined by its descriptors. -1 cost per rank.
Slow: You can only reconfigure your Variable effect outside of action time. You might need access to a lab, arsenal, spell-book, or other special equipment, or need to perform certain procedures or rituals. It takes at least a minute, possibly as long as an hour or more. The GM sets the specific time in cases where it matters, but it should be short enough that you can reconfigure between scenes in a game, but long enough that you effectively cannot do it during action time. The GM may allow you to spend a victory point to reconfigure your Variable effect during action time as a power stunt, if circumstances warrant it. -1 cost per rank.