Arcanist's Arbalest

A small but blocky cranked crossbow of dwarven design. There are four rings around the groove for the arrow, each capable of spinning independently, each one is set with chips of emeralds and a clear glass prism. 

You have a +1 bonus to attack and damage rolls made with this magic weapon.

Reserve: As an action, a spellcaster can store a spell within the crossbow. Up to 4 levels of spells of any combination (i.e. one 4th level, two 2nd levels) can be stored within the crossbow. The spell caster does this by touching the glass prisms and casting the spell with all of its normal costs but with the only effect being that the spell is stored. The crossbow can not hold any spell that requires concentration, nor a spell targeting multiple creatures.. If a spell can target one creature or multiple, it must be cast as though targeting only one creature. 

Arcanist's Arrow: When a creature attuned to the crossbow makes an attack, they can empower their next shot with a spell that is stored in crossbow. If the spell requires an attack roll the caster makes an attack roll using the crossbow. If the spell has a casting range of touch, the caster makes an attack roll with a hit fulfilling the touch requirement. On hit the crossbow deals its normal damage then the effect of the spell. The spell uses the level slot, save DC, and spellcasting ability of the original caster. The Point of Origin of any spell cast this way is where the arrow hits. If the area of a spell is a Line or Cone, it follows the trajectory of the arrow.

Proficiency with a Light Crossbow allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, proficiency with light crossbows., Damage, Combat, Ammunition, Loading, Range, Two-Handed, Slow