The HC-XD (Hover Capable-eXplosive Device) is a Scorestreak in Call of Duty: Black Ops III. It functions similarly to the RC-XD from Call of Duty: Black Ops, but has hover capabilities. It can perform double jumps, and is capable of driving on any walls that a player can wall run on. It will hover along the surfaces of water, making it unable to drive underwater. It can also receive a boost of speed by pressing its corresponding button.
The corresponding buttons for boosting and jumping can be seen on the HUD.
The HC-XD has very little health and will be destroyed in one shot from all weapons, awarding the player who destroyed it a point bonus. It will still explode when destroyed. A friendly HC-XD will have a tan and blue color scheme and an enemy HC-XD will have a black and red color scheme.
The HC-XD should be thought of as a powerful bomb that can be placed anywhere on the map. This makes it useful beyond killing enemy players, as it could also be used to destroy enemy scorestreaks such as sentry guns or even Talon units with a well timed jump.
In most cases, a player with Flak Jacket will survive the explosion if they have full health when the HC-XD explodes. However, as of a recent patch, a damage buff enables the HC-XD to kill a enemy with Flak Jacket, provided it is close enough.