Gumshoos is a long-bodied Pokémon similar to a mongoose. While it moves on all fours, it is capable of standing on its hind legs with its hands locked behind its back, similar to a human. Most of its coat is brown with a yellow underside that extends over the top of its tail. It has an additional yellow stripe that starts on its forehead and ends between its shoulders. There are tufts of fur near its shoulders, hips, and around the base of its tail. These tufts in combination with its yellow underside create the impression of an open trenchcoat. Its ears are rounded with a small notch and are located on the sides of its head. It has a short snout with a pink nose, a large mouth full of pointed teeth, eyes nearly hidden under its yellow stripe, and tufts of yellow fur on its chin. There are three black claws on each of its four short legs. Despite its length, Gumshoos is thick-bodied and has a wide, flat tail with longer fur on the tip.
Gumshoos hunts by patiently waiting along its prey's known travel routes and pouncing when the unsuspecting prey comes along. Due to its tenacious personality and ability to withstand intense hunger, it is able to wait for its prey for long periods without eating. Its favorite prey are Rattata and Raticate, but since Gumshoos is diurnal, it rarely encounters them. It is also known to prey on Skwovet. Once the sun sets, this Pokémon's stamina is depleted and it will fall asleep where it stands. It is not originally from Alola, and was brought over to take care of Rattata outbreaks. Prior to Generation VIII, Gumshoos and its pre-evolved form, Yungoos, were the only known Pokémon that could have Stakeout as an Ability.
Yungoos, the Loitering Pokémon. Gumshoos, the Stakeout Pokémon. Both are Normal types. Yungoos have sturdy fangs and jaws, and when they evolve into Gumshoos, they gain a certain tenacity and patience.
Of all Totem Pokémon that can be battled in Alola, Totem Gumshoos is one of the only two Totem Pokémon that is battled in only one game out of the two versions — in this case, Sun and Ultra Sun. The other is Totem Raticate.
Gumshoos's Ultra Sun Pokédex entry seems to reference how the small Indian mongoose was introduced to Hawaii in order to counter rat problems on sugar cane plantations, although the mongoose later became an invasive species.