Eggrobo

Eggrobos are enemies from the Sonic the Hedgehog series. They are robotic enemies that resemble Dr. Eggman. They first appeared in Sonic & Knuckles, as a standard enemy in Sky Sanctuary Zone in Sonic's story, where they hover around and shoot laser beams if they spot the player, and as a singular character and primary antagonist in Knuckles' story, where it functionally replaces Dr. Eggman in most cases. In later games, they are replaced by many variations, including the stronger, specialized, and limited-production E-100 series (culminating with E-123 Omega) and the weak, versatile, and mass-producible Egg Pawn and Flapper lines.

Super Smash Bros. for Nintendo 3DS
Standard Eggrobos first cross over with the Mario franchise as enemies in the Smash Run mode in Super Smash Bros. for Nintendo 3DS. Using the booster attached to their back, they hover around like in the original game, and try to dodge player's attacks. They use their guns to attack the player, which they will shoot smaller beams and larger beams.

Mario & Sonic at the Olympic Games Tokyo 2020
In Mario & Sonic at the Olympic Games Tokyo 2020, five Eggrobos using their original "boss" sprites appear as Dr. Eggman's teammates in the Tokyo 1964 volleyball.