If you download that Mac toolkit, it includes all of the developer tools that are needed to unlock/root/etc. That includes adb, fastboot and mfastboot. It's nice because it's all in the same location and you don't have to download the entire SDK.
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Moto X - Navy Blue with Silver Accents, Bootloader Unlocked, Rooted, Xposed (How do you like them apples, VZW?)