Hydra

Hydra may refer to the following:
*Hydra (code) - A UNSC code word for biological threats.
*Hydra system - A colony system of the UNSC.
*Hydra System Massacres - A group of conflicts in UNSC history.
*Multiple Launch Rocket System-1 Hydra Gyroc Launcher - A missile launcher introduced in Halo 5: Guardians.