Scrap WelderHow it works & interactions with other cards

Trading Up to Trade Down

Scrap Welder's ability requires two costs: tapping the creature and sacrificing an artifact. The mana value of the sacrificed artifact, referred to as X, determines what you can bring back. Crucially, the target in your graveyard must have a mana value strictly less than X. If you sacrifice an artifact with mana value 4, you can only target cards with mana value 3 or less.

Resolution and Haste

When the ability resolves, the chosen artifact moves from your graveyard to the battlefield. The ability also grants that specific permanent haste until the end of the turn. This is particularly useful for artifact creatures that have activated abilities requiring them to tap, or for those that need to attack immediately to impact the board state.

Timing and Targets

You must choose a legal target in your graveyard at the moment you activate the ability. You cannot sacrifice an artifact and then decide to target the exact same card you just sacrificed, because the target must be in the graveyard before the costs are fully paid. Furthermore, if the sacrificed artifact had a mana value of 0, you cannot return anything, as there are no mana values less than 0.

Common Mistakes

A frequent error is trying to swap two artifacts of the same mana value. Remember the 'less than' rule: a 4-drop cannot return another 4-drop. Additionally, if the targeted artifact card leaves the graveyard before the ability resolves, the entire ability fails and you do not get your sacrificed artifact back.

Interaction examples

Value Engineering with Solemn Simulacrum

Solemn Simulacrum

You control Scrap Welder and Solemn Simulacrum (mana value 4). You activate Scrap Welder, sacrificing Solemn Simulacrum. Because the sacrificed artifact's mana value (X) is 4, you target an artifact in your graveyard with mana value 3 or less. As costs are paid, Solemn Simulacrum's 'dies' ability triggers, allowing you to draw a card. The Welder's ability then resolves, bringing your chosen target to the field with haste.

Sacrificing Large Golems

Roaming ThroneSolemn Simulacrum

You have Roaming Throne (mana value 4) on the battlefield and Solemn Simulacrum in your graveyard. You tap Scrap Welder and sacrifice Roaming Throne. Since X is 4, you can target Solemn Simulacrum (mana value 4 is not less than 4, but 4 is greater than the Simulacrum's 4? No, wait). If you sacrifice Roaming Throne (MV 4), you can target Solemn Simulacrum (MV 4)? No, the ruling states it must be less than. Therefore, if you sacrifice Roaming Throne (MV 4), you must target an artifact with MV 3 or less. If you sacrifice a higher MV artifact instead, you could return the Roaming Throne, which would then gain haste.