A type of Mook native to the Stealth-Based Mission and the No-Gear Level, which patrols around a certain area and alerts its allies if it spots something suspicious or an intruder. In Stealth Based Games, these sorts of enemies must be evaded, knocked out, or killed in a certain way lest other mooks discover their downed ally and/or the player or even cause a game over.
Compared to regular Mooks, they can be nearly the same except having equipment used in monitoring for intruders and may have devices to alert allies such as alarms. They may be accompanied by dogs, or some fantastic counterpart, which assist them in sniffing out enemies and attacking them. Alternatively they may use Surveillance Drones for the same purposes. Stat-wise, they may be frailer than regular Mooks so they can be easily dispatched if done properly.
Typically these sorts of Mooks are classified as "security guards" or just "guards".
More often than not, Patrolling Mooks tend to be Invincible Minor Minions that the player cannot fight back against. At best, the player character will be locked in a Cardboard Prison when caught; sometimes Patrolling Mooks have to catch you to transport you there, and other times it only takes them spotting you for your character to surrender on the spot (often despite having previously proving themselves capable of defeating any other mook with one hand behind their back). At worst, Patrolling Mooks will be similar to the Instakill Mook in that they can One-Hit Kill your character, if not causing an instant Game Over as soon as they see you. As a result, the former variant are usually more annoying than deadly, while the latter are real threats.
- Touhou Doujin: Dawitsu's Folly: Ran Yakumo is notably the only Shikigami of Dawitsu shown to be capable at dealing with intruders.
- In the Discworld of A.A. Pessimal, the Guild of Assassins teaches strategies for dealing with anyone guarding the client, as it is considered to be bad manners and exceedingly poor professional technique for the Assassin to inhume anyone other than the client they are contracted for. Assassins are also taught to be polite and courteous to servants and hired help, in whatever context they encounter them. Therefore there are strategies for incapacitating bodyguards, footsoldiers and all those others who might come under the general heading of "mook". This might, for instance, involving dropping a quantity of an ergot-based psychotropic drug in the tea-urn, so that the guards have an altered state of consciousness for a few hours in which black-clad Assassins (if glimpsed) are taken to be part of a bad trip.
- Rio Lobo: The bad guys have henchmen marching around parts of town at night (who Cardona narrowly evades) and doing the same to guard the Big Bad's ranch.
- Inverted in Superman II: Non, one of the bad guys, kills a guard with a Neck Snap, but not before the guard activates a device on his belt and raises the alarm.
- Dungeons & Dragons.
- A number of adventures have included guards who can summon reinforcements.
- T1 The Village of Hommlet. When one group of guards is encountered, they make a low hooting sound that brings more guards. If they're being defeated they start howling, which summons all of the remaining opponents.
- T1-4 The Temple of Elemental Evil. A group of hobgoblins will strike a gong to alert other nearby guards and bring them to attack.
- Dragon magazine #132 article "With All the Trappings": a guard in the Grey Griffon Inn can pound on a gong with a mallet and arouse the entire inn.
- Dragon magazine #64 article "The Assassins' Run". In the Forgotten Realms campaign setting, the Shadow Thieves use the title obstacle course for training purposes. In one of the rooms, trainees must prevent two guards from striking an alarm gong or they will fail the course.
- A number of adventures have included guards who can summon reinforcements.
- Castle Wolfenstein: If one of the guards sees you while you aren't wearing a uniform (and for SS guards, even if you are), he will call out to alert other guards and possibly activate an alarm.
- The purpose of the regular soldiers in Metal Gear Solid 2: Sons of Liberty. When they see you, they'll call for back-up and more heavily armored and better organized soldiers will arrive to assist; these guys are the real killers. These regular soldiers are little threat on their own (except on higher difficulties) and the real threat they pose is calling in these kill-squads.
- Batman: Arkham Asylum and Batman: Arkham City: Later in the game, Mooks will have devices on them that alert each other if they are knocked out, causing the rest to be more cautious and more scared.
- Most Pre Existing Encounters in Final Fantasy XIII who aren't nailed to a particular spot are this. They are usually easier than stationary enemies because you can get a preemptive attack on them while their back is turned.
- BioShock Infinite: The Boys of Silence act like this; if they detect you they will call in other opponents to attack you.
- Detention: Once you approach a lantern spectre, Ray needs to hold her breath and don't look at it the moment it lowers its head to check on her. It will strangle Ray to death once it spots her, should she fails to do any of the actions
- Dishonored: City Watchmen, Overseers, Street Gangs, and even Assassins.
- Zone of the Enders: In the first game. In the map screen, you can see their patrolling routes and where they are.
- The Legend of Zelda: Skyward Sword: The Watcher awakens Guardians in the Silent Realm when it spots Link.
- Most mooks in the Metal Gear series.
- The first Boktai game focused heavily on this mechanic, which was found less and less as the franchise moved on and strayed away from stealth. Lunar Knights brought back these guys in the form of nasty Demonic Spiders that were quick, hard to avoid, even harder to kill, and would one-shot you in exactly 10 seconds if they spotted you.
- Ustanak makes use of little flying bug things at one point in Resident Evil 6 to hunt you down. You had to sneak up and kill them from behind, and if one spotted you you'd better run for dear life for that dumpster. Making matters worse was that Ustanak would figure out to check the dumpster on the third time.
- Danganronpa Another Episode: Ultra Despair Girls: The Siren Monokuma sounds the alarm on its head to assemble other Monokumas if it spots Komaru.
- The Stormvermin Patrol Skaven from Warhammer: End Times- Vermintide. They consist of 4-6 Heavily Armored Elite Mooks that patrol a stretch of area, which can easily take down heroes very quickly. Naturally, the best way to deal with them is to find a spot that's far from their patrol route and avoid them altogether.
- Security guards in PAYDAY 2 may patrol the various locations you are trying to rob. They'll raise the alarm if they see you or evidence of your activities, or if you fail to answer their pager in time after killing one.
- A Very Long Rope to the Top of the Sky: Sneaking into Avishun Castle means sneaking around guards that move in set patterns, leaving blind spots that you can use to sneak around.
- In FTL: Faster Than Light, you may stumble upon Rebel ships that will start charging up their FTL engines the moment they spot you. If you let them jump away, they will alert their fleet about your position, making it advance twice as fast on your next jump.
- Desperados Wanted Dead Or Alive: In one mission mid-game, there's one specific kind of Mexican bandit (wearing a blue jacket) that will run off to alert the boss if alerted, failing the mission (unless you kill them midway through, which is hard since they runs off down a road crawling with their buddies). They're dilligent to the point of immediately pegging it if they hear Cooper's watch chime or see Kate Show Some Legnote .
- Data vaults in Warframe's spy missions frequently feature guards that will run to trip the vaults Self-Destructing Security when they spot you. Grineer vaults in particular feature sensor regulators which will trip the alarm the moment you get into their cone of view or land a non-lethal hit on them.
- Both machines and humans make use of these in Horizon Zero Dawn. Watchers are unsurprisingly one of the most frequent enemy types used for this purpose. Aloy's Focus can highlight the tracks of patrolling mooks to make it easier to evade or ambush them.