So there are two formats: Commander and Duel Commander.
Commander is the original EDH. Their website is here. Sol Ring is legal in this format (mostly due to nostalgia/"cool plays"/multiplayer politics balancing) and Emrakul is not. When you see a side event at a GP or SCG Open, it typically played with this banlist and is usually multiplayer in nature (4-5 man pods). The cards on this ban list typically are abusive in multiplayer (Biorhythm or Emrakul), just broken in general (Black Lotus, Moxen), or very expensive since it would be an autoinclude (Library of Alexandria, Time Vault).
Duel Commander is an offshoot of normal Commander and was previously known as French EDH. Their website is here. Sol Ring (and most "good" fast mana) are banned and Emrakul is legal. Duel Commander events are typically by themselves although they do occur as side events in Europe for Bazaar of Moxen and other eternal-format tournaments. The cards on this ban list are just the generally broken cards (Lotus, Moxen) and specific cards and commanders that have proven to be over-the-top-dominant. They try to achieve balance between control, combo and aggro and its metagame and cards look a lot like Legacy as a result.
That is probably the second best Leyline ever. Might even be the best. Considering Ivory Mask costs the same as this Leyline (well, I guess assuming it does)...yeah I think it is. Sick card....now where does it fit in Standard?
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Commander is the original EDH. Their website is here. Sol Ring is legal in this format (mostly due to nostalgia/"cool plays"/multiplayer politics balancing) and Emrakul is not. When you see a side event at a GP or SCG Open, it typically played with this banlist and is usually multiplayer in nature (4-5 man pods). The cards on this ban list typically are abusive in multiplayer (Biorhythm or Emrakul), just broken in general (Black Lotus, Moxen), or very expensive since it would be an autoinclude (Library of Alexandria, Time Vault).
Duel Commander is an offshoot of normal Commander and was previously known as French EDH. Their website is here. Sol Ring (and most "good" fast mana) are banned and Emrakul is legal. Duel Commander events are typically by themselves although they do occur as side events in Europe for Bazaar of Moxen and other eternal-format tournaments. The cards on this ban list are just the generally broken cards (Lotus, Moxen) and specific cards and commanders that have proven to be over-the-top-dominant. They try to achieve balance between control, combo and aggro and its metagame and cards look a lot like Legacy as a result.
Hopefully that was useful.
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