Command Tower is the classic example: Its colorless from a deckbuilding standpoint because it doesnt have colored mana symbols printed on it, but it still fixes you perfectly in-game because it only makes colors your commander actually has
These include the normal summon/set of one monster (in face-up attack position or face-down defense position respectively), any special summons you are allowed, the activation/setting of spells and traps, and changing battle positions of your monsters, including flip-summoning facedown defending monsters into the face-up attack position
Even without Embercleave this is a lot of damage coming through, but of course we always have the Cleave
In the final season, Varis ends up making his own Ignis-like program to deal with rouge AI like the recently antagonistic Ai, which he claims is another fire vs fire situation, and returns to his anti-heroic AI hunting ways, even willing to antagonize Playmaker and his allies if they get in his way again
My Order I decided to go for value and get a max sized deck of 640 cards