Detect Invisibility. Within 60 feet of the tressym, magical invisibility fails to conceal anything from the tressym's sight.
Keen Smell. The tressym has advantage on Wisdom (Perception) checks that rely on smell.
Poison Sense. A tressym can detect whether a substance is poisonous by taste, touch, or smell.
ACTIONS
Claws. Melee Weapon Attack: +0 to hit, reach 5 ft., one target. Hit: 1 slashing damage.
Description
A tressym resembles a small cat, roughly the size of a common housecat, and growing up 2 feet (61 centimeters) long from nose to tail. their primary feature is their wings. Extending from their well-muscled shoulders, these wings are formed like a bat's, being divided into arc-segments by hollow elongated "finger" bones. However, the leathery membranes between these bones are covered in feathers. These wings have a maximum wingspan of 3 feet (0.9 meters).
Like ordinary cats, tressym stalk and pounce on their prey, using their claws and fangs to slay it. However, the ability to fly gives them a new dimension to hunt in and makes them much more dangerous to birds and insects. They can also get into aerial catfights.
Otherwise, they avoid fighting with anything larger than themselves, by flying away and hiding. If pursued by larger flying creatures, they will go to ground and seek a small hole or crevice to conceal themselves in.
Nevertheless, they are cunning and quick learners, knowing enough to scratch a foe's eyes and have learned the danger of weapons and wands held by people.