mystery booster box legal text Wizards of The Coast Magic:

Legendary Enchantment Thousand Moons Smithy When Thousand Moons Smithy enters, create a white Gnome Soldier artifact creature token with "This token's power and toughness are each equal to the number of artifacts and/or creatures you control." At the beginning of your first main phase, you may tap five untapped artifacts and/or creatures you control

Not sure which creatures to look for

Its a huge tempo blowout that provides a bit of extra damage and sometimes eats a creature, too

Thrashing Brontodon offers recurring access to answers to artifacts and enchantments, and its also one of the most reliable ways to transform Journey to Eternity, since you can sacrifice it to destroy Journey to Eternity, but Journey to Eternity will transform before the ability resolves and youll end up with Atzal and a Thrashing Brontodon

Then again, there always are the Magical rumors