|Attack||Fires explosive capsules/four bullets when they detect Takeshi|
|Abilities||Are shielded unless they are firing|
|Game(s)||Final Ninja Zero|
Sentinel robots have a vertical piece of metal which has a similar shaped piece of metal attached to it. This piece of metal emits that green laser and fires the capsule or bullets. Smaller pieces of metal are placed at the bottom of the robots. On top of them, there is a shining orange light.
Sentinel robots have the ability to levitate, like mines do. Sentinel robots move vertically and horizontally, and the direction they move can also be known by the direction their green laser is pointing. The sentinel robot's green laser emitted from the front of the sentinel robots cannon will fire four bullets or a capsule if Takeshi gets in front it. Takeshi can avoid the green laser and the sentinel robot completely by going into stealth, where the green laser will not detect it. Running into the sentinel robot will not harm Takeshi, unlike Mines.
Sentinel robots are protected by a dimly glowing green shield emitted from the center of the robot. This shield will only come down when the sentinel robot fires, which is when Takeshi gets in the way of the green laser. With their shields down, it is still difficult to kill them due to the constant dodging of the fired shots and that sentinel robots take five ninja stars to kill.
It is optional to kill them. Sentinel robots are the biggest enemy the player encounters in Final Ninja Zero. Sentinel robots are encountered sometimes in groups, but commonly encountered move about hallways, or even rarer, being stationary. Drone mines are commonly spawned when the alarm is set off, but in some rooms a sentinel robot will be spawned, but only one.
Sentinel robots will try to hunt out Takeshi when the alarm is set off, but due to their power and shield it is sometimes hard to avoid them. One tactic sentinel robots use is to move so that they are constantly moving their cannon and are stationary right on top of Takeshi, preventing him from escaping. Sentinel robots can rotate their cannon in any direction they choose, but it is only when the alarm is set off that they rotate them to keep aim on Takeshi.
When most sentinels meet a certain place, they will reverse direction and also rotate there cannon. Sentinel robots can also be destroyed by green mines, by controlling one and moving it right into a sentinel. sentinel robots although being slow move rather slowly. Later in the game Takeshi encounters upgraded versions. An upgraded version of sentinel robots is introduced in later levels of Final Ninja Zero, called upgraded sentinel robots.
A good strategy for avoiding sentinel robots is to stay inside their shield for as long as possible. Since sentinel robots can only hurt enemies outside their shield, Takeshi is perfectly safe from the sentinel robot as long as he stays inside its shield. However, any other enemy can still hurt Takeshi even if he is inside the shield.
A beta image of a sentinel robot was discovered on Simon Hunter's website. The beta sentinel looked much smaller than its final version, had a small cannon, and a different light. It also did not have a force field.
Upgraded sentinel robots
- Main article: Upgraded sentinel robots
Upgraded sentinel robots have a similar design to sentinel robots. However, they cannot be killed by Takeshi's ninja stars due to the fact that they never lower their defenses. They use cutting lasers instead of trip wire lasers, so the player must be careful as to not get in contact with the beam. The only way to kill them is by controlling a mine and moving it into them.