I've already designed a few arrows in the Aripockily's Quiver compendium, so I'm not doing too many more. This one is a nice arrow for trailing your prey, whether you shoot it into the side of an escaping creature or fire it into the back of a leaving wagon.
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This arrow whistles quietly in flight and leaves behind a colorful trail. Rangers are said to carry a number of such arrows, each enchanted with a different color to track their quarry across even the densest wilderness.
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Arrow of Tracing
Ammunition, uncommon
When you hit a target or creature with this arrow, the arrow lodges in the target until it is removed. A sufficiently intelligent creature can use an action to remove a lodged arrow.
Tracer. When you fire this magic arrow, you can speak its command word and cause it to leave behind a faint, dimly glowing, spectral trail. The trail persists for 2 hours or until you speak its command word again. This arrow's property can't be used again until the next dawn. In the meantime, the arrow can still be used as magic ammunition.
Optional Attunement. You can attune to this arrow to gain access to this property. The arrows collectively count as a single magic item; any effect that affects a magic item affects them all simultaneously. If you attune to this arrow, the trail it leaves behind becomes invisible to other creatures except you. While the arrow is within 1,000 feet of you, you also know the general direction toward it.