Dalek (The Master's Dalek Plan)

In an aborted timeline, killed Davros on Skaro during the Thousand Year War (AUDIO: From the Flames) and created an alternate race of Daleks in his place, (AUDIO: The Master's Dalek Plan, Shockwave) with which he conquered the universe, before the Daleks betrayed him for possessing "non-Dalek" motives. (AUDIO: He Who Wins)

Genesis of the Daleks
After acquiring the Anti-Genesis codes from Gallifrey during the Last Great Time War, travelled to Skaro during the Thousand Year War and ensured that Davros was killed by a bomb that destroyed his bunker, instead of him surviving due to being in his secure laboratory. (AUDIO: From the Flames) Pretending to be Davros' uncle, the Master replaced the Kaled as the Chief of the Kaled Scientific Elite, and modified Davros's original plans for the Mark III Travel Machines; the first Travel Machine unveiled used a pulse inducer to mutate Elrond into a Dalek mutant. The Master then placed the newly-mutated Elrond into the Travel Machine, creating the first Dalek; the Master then sealed the bunker, allowing the Dalek to gradually mutate the entire Kaled Scientific Elite into Dalek mutants, who then were transferred into Dalek casings. Following this, the Master ordered the Daleks to collapse the bunker entrance, before appointing the Dalek that was once Elrond as the Dalek Supreme and ordering the Daleks to begin preparing for the conquest of the universe. (AUDIO: The Master's Dalek Plan)

Conquest of Skaro
Following this, the Master ordered the Dalek Supreme and the Daleks to create 500,000 Dalek casings, while the Time Lord travelled forward in time to continue his plans. Upon arriving twenty years in the future, the Master was informed by the Dalek Supreme that 738,000 Dalek casings had been produced. The Master then made plans to ensure that the Fourth Doctor, Sarah Jane Smith and Harry Sullivan were exterminated to prevent the trio from trying to interfere with the creation of the Daleks; afterwards, the Master ordered the Daleks to create a neutron bomb that would mutate the Kaleds into Dalek mutants and render the Thals extinct. (AUDIO: Shockwave)

Betraying their Master
Thousands of years later, the Daleks and the Master had successfully conquered the entire universe, but the Daleks had gradually begun resisting the Master's orders over time. When the Master ordered a Dalek scout ship to be sent to Gallifrey to capture some of the planet's few survivors, the Daleks hesitantly agreed to his orders. Upon the ship's return, the Narvin, the War Livia Caralis and Crazlus of this timeline were sent to the Master, who revealed that he had summoned them simply because he was bored. When the Daleks overheard the conversation, they concluded that the Master was exhibiting non-Dalek emotions and motives, and interrupted the conversation on the orders of the Dalek Supreme. The Daleks then exterminated the Master, decreeing that they did not require their creator any longer.

However, this particular event in the timeline was actually a prediction of the future shown to the Master by a parallel universe Master, who had entered into an alliance with the Daleks of the Last Great Time War to erase the Master's actions from history and stop this alternate timeline from erasing all of existence. After being persuaded by the parallel universe Master to stop his Daleks from destroying all of creation, the Master was transported onto the Dalek Time Strategist's dimension ship, which was then attacked by the Master's Daleks due to the ship's nature as an element of the original timeline.

After persuading his past self to travel to the dimension ship, the Master tricked his past self into allowing Crazlus out of the Master's TARDIS, who was then exterminated by the Dalek Time Strategist, restoring the original timeline and ultimately erasing the Master's Daleks from existence. (AUDIO: He Who Wins)

Appearance
When they began developing on Skaro during the Thousand Year War, these Daleks were identical in appearance to the grey Daleks that Davros had developed on Skaro in the original timeline. However, unlike the original Daleks, these Daleks possessed a pulse inducer in place of the traditional gunstick that could fire a mutogenic pulse to mutate a lifeform into a Dalek mutant. (AUDIO: The Master's Dalek Plan) By the time they had conquered the universe in this timeline, these Daleks's gunsticks made a unique sound when they fired compared to those used by the Daleks of the original timeline. The technology created by these Daleks made a different "heartbeat" sound compared to that of the original Daleks as well. (AUDIO: He Who Wins)

Behind the scenes
In a Doctor Who Magazine preview, these Daleks were depicted with an unique colour scheme and design, having a claw and TCE-like device instead of the usual plunger and gunstick.