mtg transformers card list art:transformers s:sld · Scryfall Magic: The Gathering Search Transformers - The Brothers' War

Seat of the Synod is the king of the colored lands, because blue is the color that works best with artifacts, and Vault of Whispers is second because of Disciple of the Vault, but all of them have joined the fun at one point or another

Confidant is a bit restrictive in how you can build your deck with him in it and Goyf is just a very undercosted beater with no added value

Slap it on your team and your artifact creatures gain lifelink and come back at end of turn when they die, so swinging into open blockers stops being scary

They could also be decks with heavy restrictions, or even ones built around rule zero