Glorybringer is expensive, but still not so expensive that it wont make sense to have access to at the top of an aggressive red decks curve
*If a Kaladesh Invention is in 1 in 144 booster packs, we divide that by six to get 1 in 24 sealed pools
You're not worried about revealing it, and it's definitely worth paying as many times as you can since it causes so much combat to happen in the face of other players, and likely draws out more than four mana's worth
At worst, some of these cards at least do nothing when you miss, or at the very least the good ones aren't that big of a negative
The Rocket's Mewtwo EX is a prime beneficiary of that trend
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