Making the world better, one answer at a time. There are sixteen (16) US cups in one U.S. gallon. There are sixteen (16) US cups in one U.S. gallon..
What can be Transmuted? Elements (air, water, earth, fire, shadow and mana), some metals (such as Iron to Gold), primal elements (elements that are converted in stacks to a more powerful single item) and some gems can be transmuted to other types of items.
Infernal Machine Legendary Materials. There are a number of legendary materials required to create the Infernal Machine and then to craft a Hellfire Ring in Reaper of Souls. The 4 types of keys drop only from the KeyWardens, and the 4 Demonic Organs drop only from the Ubers. See those articles for full details.