So I've played commander for a while now and I know the rule that states you can only play cards within your commanders identity. For some reason I thought that they changed that rule sometime last year. Am I going crazy or did they actually change the rule?
Well, they changed how to define color identity to include activated abilities, but that was several years ago, hardly recent. The other tangentially related change was to remove the rule that made off-color mana production turn colorless, and that came with the release of Oath of the Gatewatch in January 2016. That's probably the closest thing to what you remember, but the actual deckbuilding restrictions are a core element of EDH and therefore unlikely to change.
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Legacy: Something U/W Controlish
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