The phrase "patrolling enemies" refers to the act of enemies actively monitoring or guarding a certain area to detect and confront any potential threats or intrusions. Full definition
Much like Metal Gear Solid on the original PlayStation, Never Stop Sneakin» asks players to sneak through a series of secret military bases and avoid the vision cones and laser sights of patrolling enemies. (gameinformer.com)
You can utilize shadows to help conceal you from patrolling enemies, or discover alternate paths to flank them altogether. (shortpause.com)
Patrolling enemies somehow manage to get their routs muddled up, ruining the already choppy flow. (ludophilelab.com)