Is it possible to do an infinite combo with those cards?
Using Arcbound Ravager I can send my Mox Opal to the graveyard. And with Scrap Trawler I can take the lesser converted mana cost from my graveyard to my hand.
The question is, can I take Mox Opal? Or does Mox Opal not have a converted mana cost?
What is the Rule I can find the solution?