Artificer's Workbench is a card designed to allow the player to take a chance at turning an Item card face-down to draw a Spell, which in some cases will be better than the effects of the Item card being flipped over. This card also works well with the spell cards Excavation. It is recommended to remove this card from the deck when not playing with Item cards.
The table in the center is a reference to the Elder Scrolls V: Skyrim's enchanting tables.
The three items floating over the table bear some resemblance to the Avengers, in which one (Captain America) uses a shield as his weapon, one (Iron Man) uses armor as his weapon, and one (Thor) uses a hammer as his weapon.
The armor is Lady Samantha's armor from Boss Monster 2, and the hammer could possibly be Maxwell the Monk's from the original.