The Eternal Dalek was a Dalek variant introduced in Doctor Who during the Eleventh Doctor's run. As part of the New Dalek Paradigm, it sported a bulkier mechanical shell than standard Daleks. Its livery was yellow and it sported black domes over its "skirt". It also featured the standard Dalek manipulator arm and blaster.
The exact function of the Eternal Dalek was never made clear during the brief existence of the New Dalek Paradigm. However, it has been speculated in Doctor Who media outside of the TV series that the Eternal Dalek acted as both a seer and advisor to the Supreme Dalek. According to Dalek: The Astounding Untold History of the Greatest Enemies of the Universe, the Eternal Dalek mutant existed out of sync with the natural flow of time and was capable of looking into the Time Vortex to see all of Dalek history. This ability allowed the Eternal to formulate strategies that would ensure the Daleks' continued survival and dominance. As such, the Eternal Dalek could have fulfilled a similar purpose to that of the Cult of Skaro.