Dragoneel

Dragoneels are gigantic eels that make their debut in New Super Mario Bros. U. These enemies have angry closed eyes that resemble those of a Porcupuffer, and large zigzag-shaped red jaws, the upper one having a pink lip. Also, they have long sleek bodies with a long purple crest running along their red backs and their underside is white with pale purple polka dots, and a long purple fin along their back. Dragoneel's wing-like pectoral fins and three-lobed caudal fin are similar to those of Cheep Cheeps. They closely resemble Gobblegut (and Fracktail) and behave similar to the Snorkel Snake as they try to encircle players with their bodies; in fact, their internal file name in New Super Mario Bros. U suggests they are directly based on the Snorkel Snake.

New Super Mario Bros. U/New Super Mario Bros. U Deluxe
In the game, they attack by chasing the player's character. They can only be defeated with a Super Star, and doing so causes it to spit out several coins. Dragoneels appear in the Sparkling Waters level, Dragoneel's Undersea Grotto and. It follows the player throughout the underwater course, while the players must avoid the monster. Throwing fireballs at its head will slow it down, but throwing them at its body will speed it up. If the player swims behind a Dragoneel and remains out of reach, the Dragoneel will begin circling the player. In a multiplayer game, it will go after the player furthest to the right of the screen. The Dragoneel is also capable of swimming through walls and other objects.

A purple-colored version of the Dragoneel also exists in the same level. They are shorter and make tighter turns, and are significantly slower. They only appear in a small location where a hidden Star Coin is found by going through a pipe.

New Super Luigi U
Dragoneels reappear in New Super Luigi U in the Sparkling Waters level, Dragoneel Depths where two of them chase the player. In this game, they can defeat enemies, such as Urchins and Big Urchins, by running into them.

Super Mario Maker 2
In Super Mario Maker 2, Dragoneels make a cameo in the background of the vertical section of underwater levels in the New Super Mario Bros. U style. They do not appear as course parts.

Mario Party 10
Dragoneels appear in Mario Party 10, hosting the Dragoneel Treasure events in Whimsical Waters.

Super Mario Party
Dragoneels reappear in Super Mario Party in the minigames Rattle and Hmmm and Rumble Fishing; they are one of the potential enemies seen during the final round of the former, and in the latter, they are fished out by players hoping to find the longest Dragoneel and thus win the minigame.