Class four droid

A class four droid or fourth-degree droid was a droid programmed for military and security purposes. Such droids tended to perform tasks wherein violence or combat might be expected. Class four droids were grouped into four major categories: security droids, which were used to guard locations; gladiator droids, which were designed to battle other droids for sport; battle droids, which were the most common variety and used in standard combat; and assassin droids, the only variety expressly designed to kill organics.

Text and facts from the “Class four droid/Legends” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.