I looked it up and it says it works like AC roll so... *shrugs* If I'm wrong, anyone can correct me.
I believe it really depends on how you imagine it. Since you're rolling Stealth and they're not actively rolling against you, you could call it a typical Stealth Skill check where the DC = the creature's Passive Perception. In this case, you just have to meet the DC in order to pass the check. Or, if you treat it like a contested skill check, then a tie means the situation remains unchanged. In the case of Stealth, that means the roller goes unnoticed I believe.
But I have often seen the "AC roll" argument used the other way around as well. Where the "Attacker wins the tie" rule is what you go to. And in the case of Perception vs. Stealth, Perception is usually what is considered the attacking roll since stealthing is inherently a defensive concept and trying to find a hidden target is considered an offensive act. So typically with this argument, the goal of a Perception check is just to MEET the defensive Stealth roll. Even with a Passive Perception, because all that basically means is that you're assuming the observer is just rolling a 10 on perception on average, rather than bog the game down with constant Perception checks.
But you could also see that last part being more in place for a player instead of an NPC since only players get tipped off to secrets if a Perception check is called.
So...long story short, it's totally open to DM interpretation, and I've actually seen it both ways before. xD I think I've usually played with "Perception is meet or beat Stealth" more often, so I assume that's the more common interpretation, but that doesn't mean the other isn't also just fine~
So yeah, however you want to roll with it should be fine! Heck, if you wanted to adjust it so that it always favors the player or always favors the NPC in terms of winning a tie because that sounds more fun to you, that's also a choice you can make~ xP
the general rule of thumb for 5e, to explain it really short hand, is 'meets it beats it'; if you're using Passives, AC, or DC's, those are target numbers to meet=beat. 5e has very rare contested roll scenarios. Even in a situation where someone is Actively Perceiving (using their Action to do the Skill Check), I personally hold onto the stealth checks made as a DC in the opposite direction.
The way I handle it is thus;
Passive perception 12 Roll stealth: 16 - I am sneaking past this person, until I do something to cause them to become wary or alerted. They roll Perception 'actively'; aiming to 'meet or beat' my 16 stealth.
Some GMs like to do a 'contested' roll, which is less used in 5e than other systems or editions, where 'ah, they're looking for you now, REroll stealth' and they roll the perception. I prefer my way because it keeps the 'DC's clean and clear, and doesn't get messy with 'who wins ties in a contested roll'. Most MONSTERS who do things like Grapple, Restrain, etc, have a DC associated with it rather than the semi-awkward contested roll mechanic used by PLAYERS when they grapple.
Considering the context with the fact that shopkeeper is showing off his maps - and that Beigeiros has mentioned knowing and being in the Elemental Chaos - I'll rule in Garnet's favour. We'll say this guy notices the movement in the corner of his eye but is too distracted by talking to Beigeiros to pay it any heed, at least right at this moment.
Today I learned that the Outlands have their own calendar, which I wish I had known earlier when starting this RP. We'll say for the sake of ease that we're currently in the last few days of the month of Nimbus, which is the last month of the Outlands' 'Spring'.
Garnet got a nat 20 (reduced to a 19 bc she dum) on that history check!
Oh wow! Garnet must have been really paying attention during Ancient Rune studies... or something.
Anyway.
Those runes are for each of the four main elements (fire, earth, water, air), the four para-elements (ooze, magma, smoke, ice) and the eight quasi-elements (radiance, steam, quartz, lightning, ash, dust, salt, void). This compass obviously has something to do with the Inner Planes.
Oh wow! Garnet must have been really paying attention during Ancient Rune studies... or something.
Anyway.
Those runes are for each of the four main elements (fire, earth, water, air), the four para-elements (ooze, magma, smoke, ice) and the eight quasi-elements (radiance, steam, quartz, lightning, ash, dust, salt, void). This compass obviously has something to do with the Inner Planes.
Oooh, veeery intriguing!
... That is, very concerning, sounds like this item of immeasurable value must be confiscated at once. For the Gods, and stuff.
I have few funny quotes courtesy of the Incorrect Quotes courtesy of the Incorrect Quotes Generator. Some of my favourites star Garnet herself.
Warning: character accuracy may be debatable, but I tried my best to pick ones that felt at least little true to the characters... or ones that just seemed funny for that particular character. Considering most of these guys haven't interacted yet, I apologise if this is not true of their dynamics.
Zaraknyvr: I keep a picture of all of us in my wallet. Whenever I face difficulties, I take it out and stare at the picture. The Squad: Awwww- Zaraknyvr: And I tell myself "If I can deal with these idiots, then I can deal with anything." The Squad: Oh.
Garnet: God is no longer with us, I’ll take over.
Garnet: I truly believe that water can solve all your problems. Mariel: Weight loss? Drink water. Aaliyah: Clear skin? Drink water. Zaraknyvr: Want to get rid of someone? Drown them.
Tanrith: I am Tanrith, I speak for the trees. Chop them down and I snap your knees.
*The gang's thoughts on stabbing* Raella: Would never stab anyone. Fyodor: Would stab someone in retaliation. Tanrith: Yells "I won't hesitate, bitch!" first. Mariel: Would stab without warning. Beigeiros: Would stab as a warning.
Zaraknyvr: Sorry I'm late, I was doing stuff. Mariel: YOU PUSHED ME DOWN THE FUCKING STAIRS!
Raella: I typed "bitch" into my GPS and guess what? I'm in your driveway. Mariel: Raella: Vroom vroom, come out already.
Fyodor, bleeding out on the ground: Blood loss? No, I know exactly where it is.
Garnet: Don’t worry, I know exactly what I’m doing. Everything is going to be fine! Aaliyah: How can you still say that? Garnet: Because sometimes, when things get tough, denial is all we have.
Garnet: We’re kind of missing something guys. Fyodor: Cohesion? Aaliyah: Teamwork? Zaraknyvr: A general sense of what we’re doing? Tanrith: And Mariel is not here. Fyodor: Oh, and that, yeah.
Tanrith: Why's it called an oven when you of in the cold food and you of out hot eat the food? Raella: ...What???
Zaraknyvr: Is there something you would like to say, Fyodor? Fyodor: Oh, there are SEVERAL things I would like to say.
Zaraknyvr: The ‘how the fucks’ and 'why are you so dumbs’ don’t matter. All that matters is that I have a new gun.
Tanrith: None of those words are in the Bible! Raella: Psalm 119:105. “And Jesus said unto his followers, should a manlet incel attempt to mansplain the blockchain to a girlboss, may she waste his time and yassify his blorbos” Tanrith: HE DID NOT FUCKING SAY THAT!
Garnet: When life gives you lemons, don't make lemonade. Make life take the lemons back! Get mad! I don't want your damn lemons, what the hell am I supposed to do with these? Demand to see life's manager! Make life rue the day it thought it could give Garnet lemons! Do you know who I am? I'm the person who's gonna burn your house down! With the lemons! I'm gonna get my engineers to invent a combustible lemon that burns your house down!
Raella: I don’t care what anyone thinks about me. Zaraknyvr: Ok. Raella: Wait, why such a muted reaction? Did that not sound cool?
Garnet: I’m a fool, not an idiot.
*The squad's reaction to being told they're the chosen one* Aaliyah: I will not let you down. Zaraknyvr: Sounds fun. Tanrith: K. Fyodor: No, I'm fucking not. Beigeiros: Do I have to be? Garnet: Please god, I am so tired.
Garnet, to Tanrith: How do you tell someone politely you want to hit them with a brick?
Zaraknyvr: I have the sharpest memory here - name one time I forgot something! Aaliyah: You left me, Mariel, and Fyodor in a Walmart parking lot at 2am a day ago. Zaraknyvr: I did that on purpose, try again.
Raella: Garnet, can you help me? All of my clothes keep disappearing for some reason. Garnet, wearing a hoodie that's 5 times bigger than their size: Spooky.
Mariel: Which way did Beigeiros go? Zaraknyvr: Well, based on the direction of the wind, the broken sticks in the corner, and the slight disturbance in the dirt, I'd guess they went left. Mariel: You could really figure it out from that? Zaraknyvr: No, you idiot, Beigeiros sent me a text. See?
*Squad is playing Among Us* Fyodor: I believe Aaliyah is innocent, I was with them the whole time. Zaraknyvr, what were you doing? Zaraknyvr: Oh, I was just murdering… I mean, nothing!
Garnet: I've connected the two dots. Tanrith: You didn't connect shit. Garnet: I've connected them.
Beigeiros: Wow, great work on the Halloween decorations. Where did you get the fake skeletons? Zaraknyvr: Fake?
Aaliyah: I've got a weapon, and I'm... admittedly VERY afraid to use it!
Garnet: Tired of just deserving better. Gonna start taking it by force.
*during a group project* Aaliyah: *does 99% of the work* Garnet: *has no idea what’s going on* Zaraknyvr: *says they’re gonna help but does not* Fyodor: *disappears at the very beginning and doesn’t show up again until the very end*
Raella: Did you just refer to a knife as a “people-opener”? Garnet: Garnet: …Should I not have?
Zaraknyvr: I’m really glad “fight me” has replaced “sue me” in the common vernacular because I don’t have money, but I do have fists and I am always angry.
Mariel: I prevented a murder today. Zaraknyvr: Really? That’s amazing! How did you do that? Mariel: Self-control.
Beigeiros: Why are you always trying to aggravate me? Garnet: To relax.
Raella: I think I mostly want to see what happens when this whole place breaks apart.
Raella: I learned a valuable lesson from this. Garnet: I’m guessing they are all horrible distortions on the lesson you actually should’ve taken away… Raella: DEATH ISN’T REAL AND I AM BASICALLY GOD!
*The gang is about to do something dangerous* Fyodor: Shouldn’t someone give a pep talk? Aaliyah: Go ahead. Fyodor: Be careful. Fyodor: Don’t die. Raella: *Holds back a laugh* Aaliyah: Great. We’re all bloody inspired.
Mariel: I hope they've calmed down... Zaraknyvr: Shut the fuck up you annoying ass pig.
Zaraknyvr: How does one turn their emotions off? Aaliyah: Okay, so first go to settings. Aaliyah: I'm a fucking idiot, I thought that said emojis at first. Zaraknyvr: No, I'm still willing to try this, go ahead. I'm at settings, what do I do next?
Aaliyah, looking at the squad: Okay, so I need to become a therapist faster.
Fyodor: Where is everyone? Aaliyah: Garnet had a nervous collapse, Beigeiros is looking after them, Zaraknyvr is trying to kill Raella, so I’m in charge. Fyodor: Oh my god! Aaliyah: I know, right?
Garnet: This is a very powerful artifact. You’d be messing with some forces we don’t fully understand. Raella: That sounds like a dare to me. Garnet: Oh my god.
Zaraknyvr: Hey, quick question. How petty am I allowed to be?
Aaliyah: How petty can you get? Raella: I once edited a Wikipedia article to win an argument I was wrong about.
Fyodor, writing in their diary with a glitter gel pen: I'm losing my sense of humanity. Nothing matters. God is dead. There's blood on my hands.
Zaraknyvr: Reverse tooth fairy where you leave money under your pillow and the tooth fairy comes and leaves you a bunch of teeth. Beigeiros: Why? Zaraknyvr, shaking a bag of teeth: Just because.
Garnet: Tired of just deserving better. Gonna start taking it by force.
Garnet: Don’t worry, I know exactly what I’m doing. Everything is going to be fine! Aaliyah: How can you still say that? Garnet: Because sometimes, when things get tough, denial is all we have.
Mariel: I prevented a murder today. Zaraknyvr: Really? That’s amazing! How did you do that? Mariel: Self-control.
Raella: I typed "bitch" into my GPS and guess what? I'm in your driveway. Mariel: Raella: Vroom vroom, come out already.
