Dalek drone
The Dalek drone was the most common Dalek model. (TV: Victory of the Daleks, GAME: City of the Daleks) They were used as the main "foot soldier".
History
The Daleks which escaped the destruction of the Crucible (TV: Journey's End) camouflaged themselves as "Ironsides" which were supposedly created by Edwin Bracewell. These Daleks were khaki-green coloured, probably because it was a self-applied paint job in order to perpetuate the deception that they were obedient war robots. Following the restoration of the Dalek race, the standard Daleks became a bright red colour, but were otherwise no different from their superiors. The original three Daleks were then destroyed by their "superior" successors. (TV: Victory of the Daleks)
While the design of the New Dalek Paradigm drone was mass-produced for some time, (GAME: City of the Daleks, COMIC: The Only Good Dalek) the Daleks ultimately chose to return to using the previous bronze design as the standard foot soldiers, possibly for practicality's sake; the red Dalek variants became an 'Officer' class, while their bronze subordinates served as the drones. (TV: Asylum of the Daleks)
