Two legs & two arms. Bipedal with digitigrade legs.
Furred. Fur length can range from short & cat-like, to about as long as a lion's mane. Fur sheds & regrows gradually over time. Secondary manes that act as "Hair" are also common.
Two ears. Ear length-to-body-ratio can range from being short like a cat's, to as long as a rabbit's. Ears are always pointed, like a cat's or wolf's.
Sharp, dog-like teeth with prominent canines.
Hooved legs; the species evolved to be quick runners.
Tail size, shape, & length, can vary. Some have tiny lil' short tails, some have big ol' fluffy tails you could probably hide a body in.
Front paws (i.e., hands) are soft & rounded; sometimes having paw-pads, though not always. They have no claws.
Snout & facial structure can also vary, but typically resemble those seen in the Carnivora order; though, like humans, Gloonsters are omnivores.
Eye pupils can contract to sharp slits, or dilate to round circles. Basically, they have Toothless eyes.