Prior to the Last Great Time War, a Dalek Scientist was responsible for providing Dalek Sec, named by the Emperor as leader of the Cult of Skaro, with a new, unique casing composed of Metalert. As the scientist explained to Sec, the Metalert casing was not commonplace as it was fused with very rare materials, namely flidor gold and sap from the extinct Arkellis flower. (PROSE: Birth of a Legend)
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