To create a spell, a caster draws energy from a realm, and applies a discipline and a shaping. The discipline determines what types of effect the spell can have, and the shaping determines how the effect is applied to the target(s). The realm influences how the effect is implemented. The caster's skill determines an event step they will roll for their spell power, and the result of this roll determines how effective the spell is. The specifics of what this means depend on what the spell is trying to do. The correct combination is important to achieve the result the caster wants, and casters generally practice with a variety of shapings, disciplines, and realms.
There are two broad categories of shaping; charged and channeled. When casting a charged spell, the caster can spend multiple seconds (up to their rank in the shaping) adding energy to the spell. Each second spent this way adds to the event step the caster will roll for their spell power, and also adds to the fatigue cost of the spell. When the caster releases the spell, they roll the spell power and spend the fatigue, and the spell's effects occur. Casting a channeled spell is different. Every second while the caster channels, they roll the spell power and spend the fatigue for that second, and the effects of that second occur immediately.
Some effects require certain target values to be reached for the desired effect to occur. For example, healing injuries requires spell power equal to the target's injury reduction (or some multiple of it). This target value must be reached in the casting of a single spell, but in the case of channeled spells, it need not necessarily be reached in a single second.
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