While the card looks awesome, you get a warning that the card is not playable in standard. It doesn't tell you that the card is not playable in any format. Not even Direct Challenge. So unless you want to exchange a Mythic Wildcard for a card you can just look at, do not craft it.
Yes, do not craft this. It's a bug that it is available, and it is not usable in any format. It's an emblem we have been testing that you'll see in an upcoming event. (We implement all of these internally as cards.)