This composite longbow is expertly carved with four grooves along the sides of the bow. When wielded, two face the wielder and two face away. Both sets of grooves are equidistant from the center of the bow. Within each groove, a +2 arrow is securely fastened, grown from the bow itself. The bonus on the arrow stacks with the bonus on the bow itself. The wielder may draw one of these arrows as a swift action. Arrows disintegrate exactly 1 round after they are removed from the bow, whether or not they have been fired.
The bow itself normally has a +3 bonus, plus doubled range. But it grows weaker as arrows are drawn and fired. After the first arrow disintegrates, for whatever reason, the bow's bonus drops to +2. The next arrow renders it +1, and the third leaves it with only the doubled range. Once the fourth arrow is gone, even that disappears, rendering it a normal masterwork composite longbow.
When an arrow is removed, the bow begins growing a new one in its groove. After 48 hours, the arrow is ready to be fired and the bow regains some of its power. The doubled range returns first, then +1, +2, and finally +3 when all the arrows are replenished. All arrows need not be expended before the regrowth process starts.