I started my Necron force with its first releases in white metal and back then decided on an unusual painting technique to mix things up (and which promised to be quick to achieve). Rather than paint the figures, I gave them a black wash and then scrubbed them after this was dry, leaving their bodies in their original metal state, which seemed quite fitting.
By the time the army had grown into a fully fledged faction for Warhammer 40k, plastic had taken over, so for the majority of newer sculpts my initial technique had to be replaced with a bright steel base colour and a black wash on top.
As the first of the plastic models I actually just finished (befitting their lore, they’d taken a long slumber in their dark tombs), this Necron Lord was painted in Runefang Steel and given a wash with Nuln Oil. Despite his style of armour being quite different from the old Immortals, I think they still make a decent fit. After all, the ruling elite had much more sophisticated materials and techniques applied to guarantee their immortality, while their soldiers were merely there to function according to their grand designs.