Defending China's airspace.
—A Sentinel ready for action
The Sentinel is a Chinese heavy anti-air vehicle capable of quickly dealing with masses of enemy aircraft.
Aside from Halftracks, China lacked a dedicated advanced anti-aircraft system to protect their "crawling wall" of tanks. Filling this gap is the Sentinel, the guardian of the Chinese forces. Sentinels are sluggish vehicles loaded with modified white phosphor flak shells, which react violently with the air when impacting with a target, burning through metal in seconds. Being a specialized anti-aircraft weapon, the Sentinel can only fire upon aircraft in order to ensure maximum effectiveness.
The Sentinel is one of the best dedicated anti-aircraft units in the game. Its weaponry is essentially similar to the flak in Red Alert 2, where the Sentinel's splash damage is more noticeable and harmful than regular flak in Mental Omega. Therefore, this unit is capable of taking down entire squadrons of air units (especially jets) if they are too close together.
Combined with its superior range and hit points to most of its counterparts, Sentinels ensure that no Chinese ground troops will be defenseless against aircraft. Though it has sluggish speed, this trait hardly matters since other Chinese units also suffer from this weakness, so Sentinels should have little problem catching up with them in shorter distances. The slower speed also meant that the Sentinel is more suitable in defending a base, where relocating and pursuing enemy aircraft is hardly a challenge.
Because of its nature as a pure anti-air unit, Sentinels should never be left to fend for themselves. While they have decent armor, dedicated anti-armor units will destroy them quickly and their slow movement speeds will not allow them to escape easily if they are caught off-guard by opposing forces on the ground.
- Sentinels first appear as a buildable unit alongside most other China-specific units in Think Different.
- In Road to Nowhere, two Sentinels are provided in the later stages of the battle in order to deal with incoming Thor Gunships. Additional ones cannot be built from the Stalin's Fist, however.
- In Juggernaut, a short time after the Epsilon attack starts, the allied Chinese commander will grant the player access to Sentinels.
- Rashidi has a limited number of Sentinels alongside some other Chinese equipment at his disposal in Obsidian Sands. Most Sentinels guard the area near his palace. It's revealed that Rashidi had formed a secret coalition with Yunru and was able to use Chinese technology. Malver also gained some Chinese units including Sentinel in the Covert Ops mission Survivors.