Each creature is surrounded by a personal field of Ether. Spellcasters are those who have learned how to warp and imprint their Ethereal fields in specific ways to produce desired effects. Divine casters’ fields are actually warped by their Deity when they perform their devotions to gain their spells. Arcane casters learn how to manipulate their fields through long and exhaustive study. As a spellcaster becomes more powerful, he learns finer control over his Ethereal field and can imprint more powerful spells and more spells of lesser power into it.
The act of ‘memorizing’ spells by a spellcaster is actually their time spent imprinting their field in order to draw forth the energies to power their spells. The caster’s Ether will remain imprinted with the desired spells for an indefinite amount of time, until cast or he is rendered dead. When a caster casts a spell he has memorized, its pattern is ‘erased’ from his field until the next day when he can memorize a new spell again. The caster doesn’t forget his knowledge of the spells he knows, but his Ethereal field can only retain so much of the exacting imprint required to cast spells, hence he can only cast a number of spells per day as given in the class descriptions.
If a spellcaster can cast more than 1 spell of a given level, he may memorize multiple castings of the same spell, each casting removing but one imprint from his Ethereal field. Spellcasters must get a good night’s rest, about 5 to 8 hours. Memorization takes about 10 minutes of time each day. Arcane spellcasters can memorize their spells at any time after they wake up, while Divine spellcasters must select a time they must pray each day in order to regain their spells.
In order to cast a spell, the caster must be free to speak clearly and move unhindered. Because of the complex nature of Arcane spells and the flow of their Ethereal field, most Arcane casters cannot wear anything more bulky than clothing or robes and must have at least one hand free. Divine casters can wear any armor they are proficient with while casting their Divine Prayer spells so long as they have at least 1 hand free and their Holy Symbols prominently displayed.