Pretty much the same as my regular knight.
Although, if you have followed my other customs, you will know that I was testing the Rit dye... and this is yet another.
Started with the black synthetic dye, then did a coat of glossy black on the armor pieces and flat black for the cloth. The cloth really did not want to take the white and I tried various types. The belt is actually gun metal for the sake of contrast.
This Retro Doctor Doom did not come with hands. I did fine 1 of his hands in my fodder but had to find other pieces. The only extra hand I know for sure is the space suit Iron Man from the Groot BAF years ago.
Also like the other knight, I did not have an armor head that would work. So for the time being, he is just using the symbiote Spider-Man head.

I haven't really seen anyone else do this. I just thought it would be a cool contrast. But I also think a Venom and Goblin would be good with it.