Gerson

 is a Vendor found in Waterfall. His shop is in a small cave located west of the houses of Napstablook and Undyne as well as north of the river where the River Person is located.

Appearance
An elderly looking tortoise-monster, Gerson is dressed like an archeologist, with a pointed beard, a large magnifying glass, and a tan pith helmet.

Dialogue
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Neutral and True Pacifist Route

 * Woah there!
 * I've got some neat junk for sale.

Buy

 * What are you looking for? [While purchasing]
 * Thanks! Wa ha ha! [After buying an item]
 * Careful with that. [Not buying an item]

Sell

 * Ha!
 * I'm trying to get RID of my junk, not get more of it!
 * Though, I've heard if you want to sell stuff, the Temmie Village is your best bet.
 * Where is it?
 * I don't remember.
 * For the last time, I'm not taking it! [Sell again]
 * For the last time, I'm not taking it! [Sell again]

Talk

 * Anything you wanna know?
 * [About yourself]
 * I've been around a long time.
 * Maybe too long.
 * Studying history sure is easy when you've lived through so much of it yourself!
 * Wa ha ha!
 * [That Emblem]
 * Eh? You don't know what that is?
 * What are they teaching you kids in school nowadays...?
 * Wa ha ha!
 * That's the Delta Rune, the emblem of our kingdom.
 * The Kingdom...
 * Of Monsters.
 * Wahaha!
 * Great name, huh?
 * It's as I always say...
 * Ol' King Fluffybuns can't name for beans!
 * [Emblem's meaning]
 * That emblem actually predates written history.
 * The original meaning has been lost to time...
 * All we know is that the triangles symbolize us monsters below, and the winged circle above symbolizes...
 * Somethin' else.
 * Most people say it's the 'angel,' from the prophecy...
 * [The Prophecy]
 * Oh yeah... The prophecy.
 * Legend has it, an 'angel' who has seen the surface will descend from above and bring us freedom.
 * Lately, the people have been taking a bleaker outlook...
 * Callin' that circle the 'Angel of Death.' 
 * A harbinger of destruction, waitin' to 'free' us from this mortal realm...
 * In my opinion, when I see that little circle...
 * I jus' think it looks neat!
 * Wahaha!
 * [The Prophecy #2]
 * What's that?
 * You want me to repeat myself?
 * Heck no!
 * Your eyes still work...
 * Go read a book or something!
 * Wahaha!
 * [The King]
 * King Fluffybuns?
 * He's a friendly, happy-go-lucky kind of guy...
 * If you keep walking around long enough, you'll probably meet him.
 * He loves to walk around and talk to people.
 * Eh?
 * Why do I call Dreemurr 'Fluffybuns?' 
 * Oh, that's a great story!
 * I don't remember it.
 * But if you come back much later, I'm sure I'll have remembered by then.
 * [About Undyne]
 * Undyne?
 * Yeah, she's a local hero around here.
 * Through grit and determination alone, she fought her way to the top of the Royal Guard.
 * Actually, she just came through here asking about someone who looked just like you...
 * I'd watch your back, kid.
 * And buy some items...
 * It might just save your hide!
 * Wa ha ha!
 * Wa ha ha!

Exit

 * Be careful out there, kid!

Genocide Route

 * Wa ha ha...
 * So you came here.
 * What a treat!

Buy

 * Don't expect a discount.

Sell

 * I wouldn't buy your chitzy garbage at knifepoint.

Talk

 * Really? YOU wanna chat?
 * [Fate]
 * Long ago, ASGORE and I agreed that escaping would be pointless...
 * Since once we left, humans would just kill us.
 * I felt a little betrayed when he eventually changed his mind.
 * But now, I think...
 * Maybe he was right to.
 * Cause after all, even though we never escaped...
 * A human's killing us anyway, ain't that right?
 * [Threat]
 * I've lived too long to be afraid of something like you.
 * Try it, kiddo!
 * ...I know you can't here.
 * Wah ha...
 * Knowledge like that is the only reason I've survived so long.
 * [Fight]
 * Eh? Fight you?
 * Nah, I'm not a hero.
 * Never was.
 * And b'sides...
 * These old bones aren't fit for fighting anyhoo.
 * One attack from you, then I'd.... well...
 * At least by talking to you, I've bought enough time for some of them to escape.
 * [Hero]
 * I'm not a hero.
 * But I know there's someone out there.
 * Someone who'll never give up trying to do the right thing, no matter what.
 * There's no prophecy or legend 'bout anyone like that.
 * It's just something I know is true.
 * That someone like that will strike you down.

Exit

 * Good riddance.

Talk
}}
 * [Fluffybuns Why]
 * OK, OK!
 * I remember it clearly now.
 * It was the monthly address at the castle, and the queen was giving her part on current events.
 * After finishing her update, she moved to pass the microphone to the king.
 * However, she didn't realize the microphone was still in her hand when she said: "Your turn, Fluffybuns."
 * The audience burst into laughter.
 * Realizing what she had said, she started laughing too.
 * After a few moments, the king held up his arms.
 * The crowd grew silent.
 * He leaned towards the microphone expression...
 * Stern.
 * "Dear citizens."
 * "Thank you for coming here today."
 * "I... King Fluffybuns..."
 * And the rest is history.
 * [Is Asgore a goat?]
 * Eh?
 * Goat?
 * Actually, that reminds me.
 * Toriel once wore a flower-patterned muu-muu...
 * Folks kept saying “nice muu-muu” to her, but she kept thinking they were calling her a cow.
 * So she never wore it again.
 * What was the question again?
 * Oh.
 * Right.
 * ASGORE.
 * He’s a real interesting type of monster.
 * The strongest type of all.
 * We call ‘em Boss Monsters.
 * When they have an offspring, the SOUL power of the parents flows into the child...
 * Causing the child to grow as the parents age.
 * But ASGORE doesn’t have a child.
 * So he’s been stuck at the same age...
 * And probably will be forever.
 * Huh?
 * What if the child is a human...? What?
 * Nah. That wouldn’t work.
 * So if ASGORE’s your father, he’ll definitely outlive you.
 * [Asgore and Toriel]
 * Oh yeah!
 * Of course.
 * Toriel was queen, and Asgore was the king.
 * It was tragic when she left.
 * Since everyone knew she was really the brains behind the throne...
 * But it was also just a teensy, teensy bit relieving, you know?
 * Those two were really insufferable together...
 * Nuzzling noses, bein' all cute n' cuddly in public...
 * Embarrassing their children...
 * They were so sweet it made me SICK.
 * Thank god those days are over!
 * [Undyne]
 * Undyne.
 * She's really come a long way since she was a little urchin.
 * I used to be a hero myself, back in the old days.
 * Gerson, the Hammer of Justice.
 * When she was younger, Undyne would follow me around, to watch me beat up bad guys...
 * Sometimes she'd even try to help!
 * Though, most of the time the folks she attacked weren't bad guys.
 * It'd be the mailman or something like that.
 * Anyhoo, I appreciated it!
 * Wah ha ha ha!!!

Trivia

 * When attempting to name the Fallen Child "Gerson", the response becomes "Wah ha ha! Why not?" and allows the name to be chosen.
 * According to Undyne, Gerson fought in the war against the humans. If this is true, this places Gerson among the oldest characters in the game alongside Toriel and Asgore, as well as the physically oldest character in the game as Asgore and Toriel don't age.
 * When selecting "Hero" in "Talk" on a Genocide Route, Gerson will say that there is someone out there who will "strike you down". This is obviously referencing Undyne, as that's her exact dialogue when encountering her on a Genocide Route, and the first true boss of the route.

Gerson