Mana Crystal (3.5e Equipment)
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A mana crystal is a crystal that stores spell energy, it can be charged by any spell caster and there is a rare self sustaining variant out there.
Generation: Any spell caster can charge these at a rate of 1 point per spell level expended (1/2 for 0 level spells). Charging a Mana Crystal takes a Move Equivalent action.
Storage: A mana crystal can store a maximum of 20 spell energy at any one time. If this is exceeded then the arcane energy placed into the crystal discharges, dealing the charger and anyone within 5ft 1d6 force damage.
Notes: A spell caster cannot regain his spells back. Spell power stored in the Mana Crystal lasts indefinitely. This can only be used by arcane energy, not psionics.
Self Sustaining Mana Crystal: These can only be made by a Crystal Mage. It is in all ways identical to a normal mana crystal except it generates a certain number of charges per hour.
Spell Storing Mana Crystal: Any spells stored inside may be cast. This takes the same action as casting normally and can be used as if it were a scroll.
Cost 500gp; Weight 1lb; A Mana Crystal has a hardness of 10 and 30 hit points.