Fill your deck up with discard effects like Demand Answers, a few super-cheap artifacts like Tormod's Crypt, and then a ton of huge, game-winning effects: Portal to Phyrexia, Threefold Thunderhulk, Platinum Angel, Wurmcoil Engine, the works
Decaying Soil You can see how Decaying Soil would work with Syr Konrad, the Grim and cards like Viscera Seer
He was covered in a mixture of bone, sharpened steel, and rusting iron, which gives him a very molten and fiery appearance
Adding cards with abilities usually associated with another ink color would fill some big holes, especially when it comes to the ink ramp
I am sure there are plenty more
Like the other commanders from 2017s Commander release, Edgar comes with an incredibly powerful eminence ability, one that helps establish an incredibly powerful board state very quickly