The Hardened Sentry is a scorestreak in Call of Duty: Black Ops III. It is placed on a singular spot, and will engage any enemies that move in front of it. The Hardened Sentry can be manually controlled, but due to its simple and straightforward operation, player control is usually unnecessary. The Hardened Sentry will not automatically engage enemy scorestreaks, which is likely the only time the player would need to assume manual control.
The Hardened Sentry is very useful when placed on vantage points because of its practically unlimited range and excellent accuracy when it is on automatic mode.
The Hardened Sentry is capable of taking a lot more damage than its previous counterparts. In addition to increased health, any attacks that come from the direction the sentry is facing will have a massive damage reduction. This increases the durability of well placed sentries as they can require two rockets from the front to destroy, but are instantly destroyed by a single rocket from behind. Enemies using Cold-Blooded perk will not be detected and killed by the sentry, unless the player is controlling it.
The player can have 3 sentries deployed at a single time.