Direct answer
Is Sol Ring good in Commander?
Updated
Sol Ring is arguably the strongest card in Commander — 1 mana for a permanent that taps for 2. It's an unwritten rule to include it in every EDH deck. If you don't play Sol Ring, you're voluntarily starting a turn behind.
More context
Why the answer is what it is
Sol Ring is banned in every other Magic format because it's so powerful. In Commander it's borderline mandatory — Wizards even prints preconstructed decks with Sol Ring in every one.
The card averages a full turn of extra mana over the game. On turn 1, it turns your $1 land drop into functionally a 2nd turn's mana. Nothing else at 1 mana comes close.
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