Infiltrator/Demolition droid

"You have been designed for this mission, to be the ultimate infiltration units."

- General Grievous Demolition droids were transforming droids which were used by the Confederacy of Independent Systems during the Clone Wars.

Characteristics
Grievous's demolition droids had three mechanical forms to transform among. To infiltrate a target, they initially appeared as sweeper/maintenance droids. Once past an installation's outer defenses, they morphed into large, heavily-armed, and blaster-resistant battle droids to secure a demolition point. Finally, they would go to another demolition droid in sweeper form and combine themselves to make a bomb to complete their mission. They appeared to have two models: vertical photoreceptors and 3 secondary photoreceptors (green-paint job) and horizontal photoreceptors with 2 extra photoreceptors(orange paint-job). This distinction only appeared when the droids were in battle droid form. One of each model was used in the creation of the bomb form. They also had communication capabilities, and their main photoreceptor doubled as a holoprojector.

History
Around 21 BBY, Count Dooku ordered General Grievous to destroy a critical Coruscant power generator utilizing covert demolition droids. Dooku's impetus was to thwart the negotiatory efforts of peace-minded Senators in both the Republic Senate and Separatist Parliament, as well as to ensure the warmongering deregulation of the InterGalactic Banking Clan. Grievous sent several demolition droids, disguised as Coruscant Sanitation Department cleaning droids, onto Coruscant. As the Galactic Senate debated the deregulation of the Banking Clan, the droids infiltrated and destroyed a critical power generator hub, plunging a section of the ecumenopolis into chaotic darkness. The immediate fear that resulted pushed the bills of banking deregulation into law.