Time War Daleks (previously known as Gold Daleks) are a hostile mob and variation of Dalek in the Dalek Mod. Their texture is based on the NSD Daleks from the revived era of Doctor Who (2005-present).
In The ShowEdit
The Time War Dalek is first seen in the episode Dalek, in the 2005 reboot of Doctor Who. The Ninth Doctor and Rose (having picked up the distress signal from the Dalek) travel to a collector's hoard in the year 2012. After discovering it, Rose touches the Dalek, only for it to absorb time energy from her and escape. The Dalek repairs itself and begins to battle its way to the surface against many staff personal. Learning it is mutating, the Dalek commits suicide, believing that its change is a negative thing.
The Daleks often pop up with this casing in the series, even after it is replaced with a more advanced model in Victory of the Daleks.