A drachma is the currency used by the gods and demigods and are usually as big as Girl Scout cookies and gold. The drachmas have various images of Greek gods stamped on one side and the Empire State Building on the other. The ancient mortal drachmas were made of silver, but the gods now will not use anything less than pure gold. A drachma can be used to summon Iris, the rainbow goddess, as payment to get into the Underworld, to pay the Gray Sisters to take you anywhere as long as its within their serving area, or as pay for sending a letter or package along the Hermes Express. Currently, the pure gold drachma is the main currency of the gods, goddesses, and demigods.
The most common use for the drachma is to send an Iris Message through the rainbow goddess. It is used for contact when nothing else is available, and is quite useful if any extra drachmas are allowed for use.
Drachmas can be used to bribe Charon to enter the Underworld.