It's especially strong in Pauper Affinity decks, giving you a lot of value for just one mana and playing into artifact burn strategies
Sure, you'll have to wait four turns until you can start attacking with it if you cast it this way, but that isn't really a problem when you consider the amount of ramp you're getting from doing so
Reducing the cost on this to 6 or 7 is very doable in the format, and while it takes a turn to get going, it only needs one attack to give you a massive advantage
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For example, Thornbite Staff is a strong card to pair with Krenko, Mob Boss
It's far more likely that we just got incredibly lucky