This amazing black artifact lets you play cards from the top of your library, and since its an artifact, you can cheat it into play with cards like Tinker or Daretti, Scrap Savant
This is a huge momentum swing, and it makes Gilgamesh a powerful top-end threat for red equipment decks or samurai-focused builds that want to flood the board with gear in a single turn
This might as well replace an Island in control-oriented blue EDH decks
Would it one of the many gorgeous, full-body paintings of Planeswalkers that shes done, or perhaps the stained-glass Basic Lands from Dominaria United
Combine counter doublers like Lae'zel, Vlaakith's Champion with extra combats from cards like Raiyuu, Storm's Edge to make Rograkh a threat your opponents can't keep up with
Clan Defiance It may not look sexy, but Clan Defiance is the best X damage spell in Gruul, and better than most Red options with its ability to shoot down two creatures as well as Blaze an opponent