one piece booster box op06 Trading Card Game Wings of the Captain Pack OP-06 [JAPANESE, 6 Cards] It also features Moria One Piece OP-06 Booster Box

and thats okay

With other complementary artifact mana sources like Thran Dynamo and Grim Monolith, decks could count on being able to get the kind of mana you'd need to justify packing the cards that would let you use the mana from Metalworker to deliver the knockout blow, and their presence lets you turn that Metalworker mana into permanent giant amounts of mana rather than just a one shot deal

I'm not here to discuss what a move like this means to WOTC, or even speculate on their reasons for putting this kind of policy into place, but it's important nonetheless to demonstrate how this would affect the market for consumers

Alternatively, if you cast it on an opponents turn and they dont deal enough damage to another opponent, you can use this to ensure that you lose 4 life and get the extra draw