Olivia, Crimson Bride Olivia, Crimson Bride works perfectly fine without other legends, but it incentivizes you to play a few extras
Ravnica: Clue Edition is a multiplayer variant of Magic: the Gathering which uses some of the concepts from the classic board game Clue (aka Cluedo outside North America)
You can set up the general context of the call ("I'm in a Magic game and I need someone outside the game to make a choice"), but you shouldn't explain anything that's going on in the game or what the consequences of their choice may be
He obsesses, reading and researching "like a man possessed," as Cloud puts it
Admittedly, Phylath pushing you toward basic lands during deck construction is a bit annoying, but the massive number of creatures it makes and the ability to hand out 4 power to a Plant creature of your choice is incredibly strong, and turns late game mana ramp into a lot of potential pain for your opponents