Fetishes are minor magical items that have a connection to spell casting. These fetishes are almost always hand crafted by a magic user, fetishes make very personal connections between a magic user and her craft.
Only a single fetish can be used to assist in the casting of any one spell. A magic users can only carry a limited number of fetishes. 4 up to level 6. 5 up to level 11. 6 up to level 20.
There are three different kinds of magical fetishes.
Battery: batteries are crafted to store power. Magic points are spent when crafting a battery, those points are then stored in the battery. Mp cost is the number of points to be stored plus 5. Battery fetishes are tied to a school of magic rather than a single spell. Magic points stored can only be used to fuel spells of that specific school. Mp spent can be done in any amounts from one to depleting the battery in one shot. Cost to make a battery fetish is 1gp. Once charges are used up the battery is dead and can't be recharged. Time to craft is one hour per 10mp charged.
Foci: Foci fetishes are tied to a specific spell. Foci are used to magnify the power of a given spell. When casting the spell the foci is tied to the foci adds it's level to the spell power of the caster. Cost to make a foci is 1gp x level (max lv4).
Every time a foci is used make a depletion roll. Roll 3d6 and subtract the mp cost of the spell, if the total is zero or negative the foci is depleted. Time to craft is 1hr per level.
Charm: charms are tied to a specific spell. When a charm is used during the casting of the spell add the level of the charm to the casting roll. Cost to make a charm is 5sp x level (max lv5). Every time a charm is used make a depletion roll. Roll 3d6 and subtract the mp cost of the spell, if the total is zero or negative the charm is depleted. Time to craft is 1hr per level.
Fetishes can also be fashioned in quick and dirty single use versions. This is more common with Foci and charms. A single use fetish cost 1/2 for materials and are depleated on a single use. These fetishes are often refered to as nacks or trinkets. Time to craft is 20min plus 5min per level or 10mp charged.