Iris was the Goddess of the rainbow in Greek mythology and also a messenger of the Gods

Iris could travel swiftly by using the rainbow. She was a messenger for the Greek gods and goddesses.

Iris, was the goddess of the rainbow, the messenger of the Olympian gods. She was often represented as the handmaiden and personal messenger of Hera.

As far as I know, Iris did not have a "weapon." She was the goddess of the Rainbow, and a messenger of the gods.

She holds a herald's staff.

She brings water from the Stynx in a pitcher. This water is for oaths for the gods.

Iris was the goddess of the rainbow. She often worked for Hera as Hermes worked for Zeus.