The Window has been used for many genres, from the most mundane
contemporary murder mystery to the most outlandish superheroic
adventure. Below are some ways to manage those exceptional types
of stories where more-than-human beings are involved, such as
superheroes, dragons, or Lovecraftian monsters.
The Shebang! Notation
One problem which arises in representing truly amazing abilities is how to fit them onto the competency ladder. Obviously there wouldn't be much variety if the actors were sitting around rolling D4s for everything -- contest rolls would be tied too often and success rolls would be mostly pointless. The basic competency ladder only represents the levels of ability that a human being can achieve; what happens when the character in question isn't really human at all?
To address this, the Window uses a second competency ladder which is "above" the normal one. A simple system called the Shebang! notation (with a nod to Larry Wall) is used to delineate these amazing traits and skills from normal abilities. It works by placing an exclamation point (!) after the die and including more specific descriptions of what the character is able to do.
For example, a character with superpowered physical strength which allows him to lift up to the weight of a car would have the following trait listing:
Amazing strength. Able to lift a car. (D12!)
The Shebang! lets you know that his strength is "superheroic," which means that he would never have to make a strength roll against "normal" tests; if he wanted to break down a door or carry a companion to safety he would simply succeed. However, if he were going up against a challenge that itself was "superheroic" in magnitude (perhaps he's wrestling with a powered up supervillian), he would use a D12 to make that roll.
The idea is that superheroic or unearthly characters exist on
a level all their own. They are so astonishing that competition
is only meaningful if it is against someone (or something) in
their own league. The important thing to do with any Shebang!
ability is to describe the power sufficiently enough that it's
at least somewhat clear what is possible with it. From there the
actors and the Storyteller can roleplay through superheroic encounters
without much slow down.
Multiple Competency Rungs
With some powers, it is difficult to assign just one competency rung and still represent the power accurately. One such case is an ability that is extremely "powerful" but rather hard to control (or vice-versa). Another is a power which works very well in certain situations but very poorly in others. In such a case, two or more competency levels can be used, each describing a different aspect of the ability.
For example, imagine that your character has the ability to throw fireballs from her hands. These fireballs are extremely deadly -- just about anything they come in contact with will be immediately vaporized (D6!). However, she's not very good at getting the things to hit where she would like (D20). Having two different rungs like this allows the Storyteller to test the aspect of the ability is in question in any given scene.