Chapter VII: Earthbound
He didn't have to worry about gainer learning about koji's real identity, or the contacts that would lead to as the perception filter automatically turned on, as if recognizing danger.
Chapter XI: Light, Part One
"oh well do what you want, most of the city seems to think you gone awol anyway, i won't tell anyone about the perception filter."
Chapter V: Brothers in Arms, Part One
“listen, don't be unreasonable, you can stay with us and we don't mind that, i just don't want to get more people hurt, they can see in cameras and that is why our perception filters are always working."
Scales and Honor: The Shattered God: Chapter 3
“you can tell by the perception filter they have up. it _doesn't_ want to be observed by any living eye." “wise for them to ward it." asterion snorted. “these wretches might actually be _smart_." “how we find if we can't look?"
Chapter XII: Skeletons in the Closet, Part Two
Upon hearing isaac yell that, finn quickly took shelter in the car and closed the door, deactivating his perception filter as isaac joined in. as whatever screamed flew over them, the car shook and dust was brought up from the ground.
Chapter IX: Fly Me to the Moon, Part Two
Finn waited for him to make an action; if he did he would simply just use his perception filter and hope for the best.
Chapter VI: Sun Going Down, Part Two
Finn drove forward, the radio becoming complete static as the perception filter knocked out service.
Chapter VI: Inferno, Part Two
Turning off his perception filter, he walked forward and looked around. a crowd was gathering around the once burning area of the new york, which seemed to be rapidly cooling off.
Chapter V: Burn, Part One
"give up your perception filter and return home, sell your apartment and return to your home, you know where i live and if you know that why haven't you returned home to your father?"
Out of Time, Out of Space (Full Story)
"well, hopefully the perception filter is still there." "perception filter?" ryt asks? "it's sort of a low-level psychic field that causes the object to be...well, not so much invisible, as just ignored.
Balance of Power Part 2: Gentleness and Curiosity
The gryphon was able to appear in public without attracting so much as a glance from anyone except his little vulpine pet, an ability he described as "a broad-wavelength perception filter, tailored to certain physical effects of my manifestation" -
Chapter V: Firestorm, Part Two
A perception filter, injected into body, allowing them to pass through his shirt. he then waited a few seconds, in case washington suddenly showed up with intension of ruining that plan. but the seconds passed and rocco decided to start his plan.