Double Wave Axe (3.5e Equipment)
From D&D Wiki
The Double Wave Axe is an exotic weapon favored by certain minotaur tribes who can handle the great weight and bulk of the weapons. Superficially they resemble orc double axes, but the axe heads are large crescent swoops, hence the "wave" part of the axe, and are often fully formed into semi-circles or rings. The handle is built to allow the hand to slide up and down with ease to key points, enabling one to fight with two heads, or simply one.
A Double Wave Axe is a double weapon. You can fight with it as if fighting with two weapons, but if you do, you incur all the normal attack penalties associated with fighting with two weapons, just as if you were using a one-handed weapon and a light weapon.
A creature wielding a Double Wave Axe in one hand can’t use it as a double weapon—only one end of the weapon can be used in any given round.