While the basic appearance of Daleks remained the same throughout their history, there were several changes and alterations to Davros' original design of the Mark Three travel machine. Variants of the "basic" Dalek design were produced both by Davros and the Dalek Emperor/Dalek Supreme (these last two representing the major power holders in the Dalek hierarchy). Both factions of Dalek used a Dalek drone for basic combat. A Dalek variant should not be confused with a Dalek using a different Manipulator arm, as these are not considered true variants.