Necrons does have their impairment, such as the monomaniacal Destroyers, or the flayed ones. Could make for a compelling, ghastly visage to have flayers appearing as blood-red rust covered Necrons. Due to the detritus of their skinpuppets, but possibly also a physical effect from the flayer sickness?
I do wonder why Nurgle havent tried to woo twitchy and nervous Necron courts over the rising number of flayers in their domain. But perhaps its because they simply dont have enough soulbits left to even draw the eyes of the dark gods.