Sushi

Sushis are a blue shark-like enemy (a mako shark) found in several Mario games. They have navy-blue colored scales and a long pointed nose. Their name comes from the Japanese dish, Sushi.

Super Mario 64
Sushis first appear in Super Mario 64, where they can be found in Dire, Dire Docks. These sharks swim around, minding their own business. There is no way to attack them and they usually won't bother Mario, unless he accidentally swims into them. They also reappear in the DS remake, Super Mario 64 DS, acting the same way as they did in the original.

New Super Mario Bros.
Sushis make a minor appearance in New Super Mario Bros., only appearing in World 1-A. IThey travel two at a time, swimming horizontally at different heights on the screen. They can be defeated with fireballs or a Starman.

Mario Party
In the Mario Party minigame Treasure Divers, a Sushi appears swimming around alongside two Bloopers.

Mario Party 2
In Mario Party 2, one appears in Pirate Land, and will ferry anyone who lands next to the dock of one island to the dock on the opposing island, charging five coins per trip.

Mario Party 3
In Mario Party 3, a Sushi appears in Deep Bloober Sea, and is in charge of the torpedo controls. This Sushi will ask everyone who passes to push one of four buttons upon reaching a fork; one of them serves as the detonator, which will fire a torpedo when pushed, forcing the player to take the path they didn't select. A Sushi is also present in the minigame, Dizzy Dinghies.

Mario Party Advance
In Mario Party Advance, a Sushi lives at Sushi Cliff. When the player arrives, Sushi appears and asks the player for help after Shroomlock was pulled into the sea. However, when Shroomlock emerged, he states that somebody intentionally pulled him into the sea, and Sushi says that he interrogated the three that were around at the time of the crime: Blooper, Cheep Cheep, and Dolphin. After listening to the alibis, the crime is solved: Blooper pulled him in, as he is the only one with arms. Sushi then gives the player the Gaddget Digitizer. The ending of the game states that Sushi opened a bed and breakfast on the cliff side.

Mario Party 7
In Mario Party 7, the 1-vs-3 minigame Be My Chum! involves the lone player calling out names of various enemies (including Sushi) on the Nintendo GameCube Microphone to attack the other players. They simply swim straight forward in a speedy manner.

Mario Party 9
In Mario Party 9, Sushis only appear on the board Blooper Beach. They appear after the player runs into a Dolphin. They advance from behind the player, moving four spaces per turn. If they catch up to the vehicle, then the player loses half of his or her Mini Stars; it is then replaced by a Dolphin. If the player is near the first Boss Battle Space when a Sushi is the active fish, it swims away. Notably, Sushis are one of the few characters seen in the game that do not have a constellation based off of them.

Mario Hoops 3-on-3
In Mario Hoops 3-on-3, the course Bloocheep Sea has Sushi swimming in the background.

Mario Kart Arcade GP DX
In one of the courses of Mario Kart Arcade GP DX, a large statue of a Sushi can be seen above the track.