Swarm Carbine Edit
A blaster weapon of Drow make, this gun has two large overlapping tanks on top, each of which channels a separate conjuration effect before mixing them with the gun's blast. When a blast hits, it also summons a swarm of large spiders composed of energy (as the spell Summon Swarm, using the stats for a Rat Swarm affected by the Elemental template).
The weapon can create swarms of any energy type, but changing energy types requires a swift action to manipulate a dial on the weapon's side.
Faint Conjuration, CL 1, Craft Magic Arms, Summon Swarm, Market Price 4900 CR (plus weapon modifications if desired)