Staff of Air

Staff of Air is an enchanted quarter staff +2 which can destroy air elementals when they are hit by this staff. The weapon deals 1d6 +2 points of crushing damage, has -2 THACO bonus, it weighs 3 lbs and it has a speed factor of 2. This staff can also be used to summon a hit dice 8 air elemental for 1 hour and Both abilities require charges from the weapon. This item appears in Baldur's Gate II: Shadows of Amn and Baldur's Gate II: Enhanced Edition. It's not known where it can be acquired.

In-game description
"Staff of Air This staff seems to draw from eleven artistic traditions, though tied less to the forest than is usually customary. It was apparently designed to control air elementals, being able to summon one as a servant to the wielder, and potentially destroying creatures of the same type in a single blow. When necessary, it can also spawn a cloud of gas causing anyone within the area of effect to fall into a deep slumber. Some effects are limited by charges."