A Mecha Cheep is a mechanical version of Cheep Cheep that first appears in New Super Mario Bros. U. They have metal fins and a wind-up key at the back similar to that of Mechakoopas.
In the game, Mecha Cheeps appear only in the level The Mighty Cannonship. They're impervious to Fireballs, but can be defeated with an Iceball or Star, or by leading a Targeting Ted into them.
Mecha Cheeps appear in Mario Kart 8 in the underwater section of Water Park and on posters seen in the building at the beginning of this course.