This burnished brass sphere of interlocking bands and gears is 3 inches in diameter and weighs 1 pound. The intricate mechanisms click and whir softly, indicating its hidden potential.

Activation:
As an action, you can insert a gemstone worth at least 10 gp into the sphere and speak the command word. The gemstone is destroyed, and the sphere magically transforms into a clockwork mouse (see stat block below). The clockwork mouse is a construct that obeys your verbal commands and takes its turn immediately after yours in initiative order. When the clockwork mouse drops to 0 hit points, it reverts to its brass sphere form in your pocket.

The clockwork mouse can be repaired during a long rest, or you can expend a spell slot of 1st level or higher as an action to repair it, returning it to full hit points.