Lantern of Tracking

This hooded lantern burns for 6 hours on 1 pint
of oil, shedding bright light in a 30-foot radius
and dim light for an additional 30 feet.
Each lantern of tracking is designed to track down
a certain type of creature, while the lantern is
within 300 feet of any creature of that type, its
flame turns bright green. The lantern does not
pinpoint a creature's exact location, however.