Crow

Crows are a species of birds that appear in several Mario franchise games, usually as part of the scenery, and are usually seen inhabiting dark and gloomy-looking places. Their first appearance as such is Luigi's Mansion, but they only gain a more prominent role in Paper Mario: The Thousand-Year Door as inhabitants of Twilight Town, and later in Luigi's Mansion: Dark Moon as enemies. In addition, several species from the Mario franchise, most notably Pidgits and Crowbers, are based on crows.

Paper Mario: The Thousand-Year Door
Crows appear in Paper Mario: The Thousand-Year Door. They appear on trees, and when Mario talks to them at first, they simply caw. When Mario uses Vivian and hides under a tree, however they say other things. Vivian explains that they only pretend to be ignorant when people are around. Only some crows give tips in the game. The crows in the game all appear only in Twilight Town. They are shown to talk about a variety of subjects, ranging from internet stocks to which university their children should go to.

At one point in the game, the crows make a reference to Luigi's Mansion.

Luigi's Mansion: Dark Moon
Crows appear as enemies in Luigi's Mansion: Dark Moon as opposed to simply being ambient objects in Luigi's Mansion. Unlike in Luigi's Mansion and Paper Mario: The Thousand-Year Door, in which they are tall and stocky, and have eyes on the sides of their heads and black feathers, they are now quite short and lean, and have eyes on the front of their heads and purple feathers. They now also appear in large swarms, whereas in the two aforementioned games, they only appeared in groups of two. They can hurt Luigi, but he can suck them up with the Poltergust 5000 or flash the Strobulb to defeat them, which makes them drop a bill or some hearts. Most crows in the game are found in Haunted Towers. Gold crows also appear and fly in a certain direction before disappearing. When the Strobulb is used on one, it drops five bills.

Luigi's Mansion 3
Crows reappear as enemies in Luigi's Mansion 3, along with gold crows, where they act as they did in Luigi's Mansion: Dark Moon. They also have a swooping attack similar to Crowbers in the New Super Mario Bros. games.

Mario + Rabbids Kingdom Battle
Crows inhabit the Spooky Trails in Mario + Rabbids Kingdom Battle and are mostly found in flocks. They are essentially black-colored little birds. As with little birds, they only serve an ambiental role and fly away when Mario and the team approach them.