All new cards are tournament legal in Vintage and Legacy, with the exception of course of the oversized commanders
You want big and expensive trample creatures, coupled together with plenty of ramp
It's so effective for multiplayer because it mills each opponent and grows based of all of the opposing graveyards, not just one player's
Since EDH lets you play any Magic: The Gathering card from any MTG set (if it's not on the Commander banlist), there are a lot of extremely scarce, extremely powerful cards in this format, and players are looking to Commander Masters to deliver some choice reprints and drive those prices down
Colors Blue, White Size 50 Cards
The trick for other decks with an aggressive enough commander is whether the full mana cost is still worth running