From Halopedia, the Halo wiki
- Use the Hydra Launcher as you would the Plasma Launcher from Halo: Reach; activate Smart-Link, plan your target, and fire away.
- As with other projectile weapons, the Hydra's missiles can be stopped by walls or other scenery objects.
- The Hydra takes 1.5 seconds to lock on to a target once the weapon has detected it. Once locked on, its missiles will track down that target.
- The Hydra is effective at damaging both land and aerial targets.
- The effective range of the Hydra when unscoped is 24.4 meters (80.0 ft) and 87.8 meters (288.0 ft) when scoped in.
- The fully automatic fire rate of the Hydra is 200rpm
- The speed of the Hydra's missiles is 31.86 m/s (104.5 ft/s)
- The Hydra's first appearance is in Blue Team, in the shipyard. It later appears in Glassed, Unconfirmed, Evacuation, Genesis, and Guardians.
- The Hydra is a powerful asset for AI-controlled Spartans, especially in the mission Blue Team. If the player playing as John-117 or Jameson Locke finds a Hydra, they should order an AI-controlled teammate to pick it up. This is most effective for characters whose default weapons are short-ranged weapons, such as Olympia Vale or Kelly-087.
- Using the Hydra near the presence of enemy Promethean Watchers is unadvisable, as they can throw Hydra missiles back at the player. If the player wants to destroy nearby Prometheans with a Hydra, they should kill the Watchers first.
- It is possible to kill the Watcher with a second Hydra missile while it attempts to deflect the first missile towards the player, but this will result in the player wasting ammo.
- The Hydra is useful for tearing through Knights and Soldiers.
- Two Hydra missiles that directly hit will kill a Spartan, while three are required to kill with splash damage only.
- If an enemy locks on to you with a Hydra, use the environment and thrust evasion maneuvers to escape.
- At close range, hipfiring is more advisable.
- Arena and Warzone feature two additional versions of the Hydra:
- Typhon: an improved version with a faster rate of fire and lock-on time, upgraded and improved recoil compensation, higher damage output, faster reload speed, and one more additional magazine. This variant is most efficiently used for more aggressive engagements or dishing out damage to vehicles.
- Echidna: an advanced version with EMP-equipped missiles, a much stronger zoom level detecting targets up to 621.79 m (2,040 ft) away, and automatic lock-on even without Smart-Link activated. This weapon can be used to facilitate boarding or hijacking action on or otherwise do great damage to enemy vehicles, and is especially useful against aerial Warzone bosses (e.g. Phaeton Helmsmen).