Chalkydri
Chalkydri (Ancient Greek: χαλκύδραι khalkýdrai, compound of χαλκός khalkós "brass, copper" + ὕδρα hýdra "hydra", "water-serpent" — lit. "brazen hydras", "copper serpents") are mythical creatures mentioned in the apocryphal Second Book of Enoch (1st century CE), often considered an angelic species.