Juggernaut war droid

"When the war droids breached the armory, the uprising became a catastrophe. They were juggernauts, and for them it was as easy as returning home."

- Conflagration: An Eyewitness Report of the Great Droid Uprising

Juggernaut war droids were types of battle droids used by various factions throughout the galaxy in the times before the fall of the Galactic Republic.

Characteristics
The juggernaut operated in a bipedal configuration, and had two alternate methods of propulsion. It could use twin outrigger jets to propel itself into the air for bursts up to one minute, or the jets could convert into intake propellers for underwater use. Unfortunately, the droids propellers would often jam, sinking the droid. The juggernaut was armed with a wide beam sonic stunner, a high powered shatter beam, and had also been known to carry pulse wave rifles.

History
They were first commissioned in 4,800 BBY by Supreme Chancellor Vocatara, and they quickly saw service in the Gank Massacres. During the Great Droid Revolution, however, they were used by HK-01, shredding the Republic rocket-jumpers in an air battle over Monument Plaza. They were quickly decommissioned after HK-01 was deactivated.

Ilum, an Iron Knight, and some of her twelve children lived inside the bodies of Juggernaut war droids. Arden Lyn's cybernetic arm came from Juggernaut droids.

The Mandalorians later used the JU-9 Juggernaut War Droid.