Not sure if Joiner Adept is the way to go in that deck; sure, you can tap your Urza/Cloudy stuff for colored mana, but only one colored mana rather than 2-3 colorless. I'd be more tempted if you used Vernal Bloom instead for the more mana; that way all your Forests would tap for G+whatever.
Also, why 4 Doors? They aren't really useful early, and with all your land thinning, you should be able to draw into one eventually. If you're worried about Shatters, put in Eternal Witnesses. If they blow up your Door, you can fetch it right back; and early game, the Witness can refetch a Reap & Sow to get more mana.
Also, why 4 Doors? They aren't really useful early, and with all your land thinning, you should be able to draw into one eventually. If you're worried about Shatters, put in Eternal Witnesses. If they blow up your Door, you can fetch it right back; and early game, the Witness can refetch a Reap & Sow to get more mana.
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