Arcane Battery

While attuned to this item and the battery is drained, you may expend a spell slot of up to 6th level to to imbue this battery with arcane energy.  When imbued in this way, the battery has a number of charges equal to the level of the spell expended. As an action at the end of a Short Rest, you may expend any number of charges to restore spellslots at the cost of one charge per level. Alternatively, you may expend energy from the battery to recharge other magic items such as a Wand of Magic Missiles or a Rod of Resurrection. When you use the battery in this way, the cost of restoring a charge is decided by the level of spell the item casts. For example, restoring one charge on a Wand of Magic Missiles costs one charge from a battery but restoring one charge on a Rod of Resurrection costs six battery charges. Items which cast only cantrip level spells may be fully recharged so long as at least one charge exists in the battery. Finally, this stone can operate as a heatless torch which lights on a command word you choose and provides bright light in a 20-foot radius and dim light for an additional 20 feet.

While the fully charged battery is on your person, if you are hit by a spell attack roll a d20. On a 1, the battery violently discharges dealing 2d10 lightning damage to the the attuned caster and 2d6 lightening to all creatures within 10ft.

Notes: Spellcaster