I'm not going to do the bit where I pretend we both don't know who we're talking about today, so let's just do the reveal already
Honorable Mention: The Elder Dragons You cant really talk about whats important to the format without the five creatures that gave it its initial name: Arcades Sabboth, Chromium, Nicol Bolas, Palladia-Mors, and Vaevictis Asmadi
The only time it is actually zero cost to run a colourless land is when you are mono, you have no double colour two drops and you will not be keeping any 2 or fewer land hands
I like to give my other legends prowess in my legends deck in any format as what I see as the most obvious use case for Bria, Riptide Rogue
When you do, return target instant or sorcery card from your graveyard to your hand
You can send 1 card to GY with this card in your hand and his Spell Trap as a cost