Strategist Dalek (New Dalek Paradigm)

The Strategist Dalek was one of the new species of Dalek that emerged from the Progenitor in 1941. As it's name suggests, it was in charge of battle strategies and operations.

History
The first Strategist Dalek destroyed an "Ironside" Dalek and the leader gold Dalek. It worked most of the machinery inside the Dalek ship and escaped through the time corridor with the Supreme Dalek, Eternal Dalek, Drone Dalek and Scientist Dalek. (DW: Victory of the Daleks).

Later, a number of Strategists would be seen in the Supreme Council Chamber on a restored Kaalann, alongside the new Dalek Emperor, who was also coloured blue. (VG: City of the Daleks)
 * They may have acted as the Emperor's Personal Guard or members of the Dalek Council.

Personality
The Stratagist seems to be the only one of the other three colored Daleks, not including the Supreme Dalek, that speaks, and appears to always stay close to the Supreme. When it first exits the progenitor machine, appears next to the Supreme. Second when it stands next to the Supreme while saying "Shields intact. Pulse still active". It then appears on the TARDIS screen standing close by the Supreme, while the Supreme reveals about Bracewell being a bomb. It could be that the Blue Dalek is a very eager, if not loyal, Dalek. It's voice appears to be somewhat higher and it speaks very quickly.

Behind the scenes

 * According to Doctor Who Confidential, the name "Strategist Dalek" was coined by Mark Gatiss as one of the new styles of Daleks. Gatiss also coined the names of the White Supreme, Drone and Scientist Daleks.
 * Matt Smith stated in Confidential that the "blue" Dalek was his personal favourite of the five Progenitor Daleks.
 * Although the Supreme, Drone and Eternal have appeared in The Pandorica Opens and The Big Bang, the Strategist and Scientist do not appear.
 * The Strategist Dalek appears to have a reversed colour scheme to the original footsoldier Daleks from 1963-1967 which had Silver bodies with blue orbs while the Strategist has a Blue body and Silver orbs.