Scorpia and Lonnie in the episode “Roll With It".
Its ‘head’ is a chrome sphere with a small vertically moving camera and an antenna. It has three articulating legs which help it move. It can be remotely controlled and can relay audio and visual recordings.
Presumably, it was created in the Fright Zone by Hordak or Entrapta.
It was used to spy on Adora and the rest of the princesses while they were planning to attack a Horde controlled tower; it broke when Mermista accidentally spilled a drink on it.