Lab
The Lab (JP: ラボ), or Laboratory (JP: ラボラトリー), is the workplace and home of the Royal Scientist, Alphys. It is a building in Hotland, where Alphys conducts her studies, controls sections of Hotland's puzzles, and surveys the majority of the underground through hidden cameras.[1][2] It also houses the True Lab.
- A package of Instant Noodles can be obtained from Alphys's fridge.
- Alphys and Mettaton make their first appearances here, with the latter subjecting the protagonist to a quiz show.
- The True Lab, initially referred to as a "bathroom", is found here, containing Amalgamates, the results of Alphys's ill-fated experiments with determination.
After escaping Undyne on the Neutral Route, the protagonist arrives at the Lab's entrance. Inside, the lights are off, and the protagonist cannot inspect anything aside from the monitor since it is too dark.[3] Halfway through, Alphys exits the "bathroom", turns on the lights, and introduces herself. She explains that after watching the protagonist, she wishes to aid them.[4] However, Alphys warns them of Mettaton, a murderous robot she created. Shortly after, Mettaton breaks through the wall and subjects the protagonist to a quiz show.

Afterwards, Alphys notices the protagonist's dated Cell Phone and upgrades it. She immediately excuses herself to go to the "bathroom", rendering it inaccessible.[5] Once the protagonist exits the Lab, Alphys realizes that she did not watch the encounter between Undyne and the protagonist.[6] As the protagonist ventures through Hotland, some of Alphys's UnderNet statuses is of her taking pictures in the Lab,[7][8] including taking a picture of a bowl of Instant Noodles with a "catgirl figurine".
Following the fight with Mettaton EX, the doors to the Lab are locked, rendering most of Hotland's first floor inaccessible.
In the Alphys Ending of the Neutral Route, it is implied that Alphys evacuated the surviving monsters to the True Lab. Alphys tells the protagonist that she knew she had to do something about their actions, even if it meant that the monsters would learn the truth about her.
On the True Pacifist Route, the protagonist goes to the Lab to deliver Undyne's Letter to Alphys. Alphys reluctantly opens it[9] and mistakes the protagonist for the writer of the letter. She then goes on a "date" with them in the garbage dump, with Undyne herself and Papyrus making appearances. After Papyrus and Alphys's training, Papyrus sends her back to the Lab and calls the protagonist to recommend they go there as well.[10]
The protagonist can explore the Lab to find new objects. Inspecting the garbage can between the computer and monitor reveals that someone sent an intimidating message to Alphys, "I KNOW WHAT YOU DID." The "bathroom" is open, and near the doorway is a note from Alphys addressed to her friends. In the notes, Alphys says that she needs to face her mistakes and that "the truth" is past the door. On the second floor, Mettaton's deactivated body can be found on Alphys's working table.
When the protagonist enters the door, it is revealed to be an elevator that descends into the True Lab.
On the Genocide Route, Alphys watches the battle between the protagonist and Undyne in her Undying form.[11] The lights in the Lab are already on, and Alphys is not present. Instead, Mettaton explains that Alphys has been evacuating everyone to a safe location and leaves after the protagonist approaches him aggressively.
The Lab is a large white and red building with a pale green interior. There are two floors on the lab, the ground floor being Alphys's workplace, and the second floor being her room.[12] Three conveyor belts are also in the Lab, with two leading to the other floor, and one on second floor that moves to the left.
On the ground floor, the dialogue for the Alphys's monitor and dog food varies varies depending on the protagonist's progress.
For the monitor:
- When the lights are off, the dialogue becomes "It's you...?"
- When the lights are on, the dialogue explains the monitor's use.[13]
- On the Genocide Route, the dialogue is, "It's me, <Name>."
For the bag of dog food, it is described differently based on if the protagonist has killed any monsters.
- If no monsters were killed, it is described as "half-full".
- If any monster is killed, it is described as "half-empty". A follow-up message, "(You just remembered something funny.)" appears if Doggo, Lesser Dog, and Greater Dog are killed and the protagonist has 21+ kills.
If Papyrus is called a second time on the first floor, he recalls seeing the dog food bag in Sans's room and asking Sans about it.[14]
The ground floor also includes a "cute" garbage can,[15] a messy computer desk with papers and bowls, a fridge filled with Instant Noodles and soda, a bag of dog food, and the elevator, which has a bathroom sign beside the door. After Mettaton's appearance, there is a hole in the wall between the elevator and the dog food.
On the True Pacifist Route, the garbage can contains a crumpled paper with the words, "I KNOW WHAT YOU DID." On Alphys's computer desk, there are papers that are implied to be for a game walkthrough written in "chicken scratch", the computer itself, which has access to Snowdin's Multicolor Tile Puzzle,[16] a teacup from Asgore[17] filled with soda, and figurine of a "female human with cat ears". Inspecting the hole has the narrator note that the space is only a few feet wide. On the Genocide Route, it is described as being there to "complete the look".[18]
On the second floor, there are five shelves, four labelled as "Human History:"
- Light green: Dusty scientific books.
- Green: Books, with one being a comic of a "giant robot fighting a beautiful alien princess".
- Yellow: VHSes and DVDs of cartoons.
- Blue: Books, with one being a comic of "Two scantily clad chefs [...] flinging energy pancakes at each other."
- Red: Books, with one being a comic of a "hideous android" running late to school.
Next to the shelves is an implied ice cream machine that converts Waterfall's "scientifically important" seaweed,[19][20][21] a number of tools, a big, dusty work table with a chainsaw and a paper depicting SOULs, a poster of a character resembling Mad Mew Mew above it, a closet with a dress from a friend (alluding to the possible date with Alphys),[22] a shelf with unopened letters from monsters[23] and a lamp with pink fish, a compacted bed[24] with a pink heart poster above it, and a signed poster of Mettaton's TV premiere.[25]
On the True Pacifist Route, Mettaton's deactivated body can be found on the second floor.

In the UNDERTALE Art Book, Toby Fox states the entire lab was sketched out by Temmie, but the spritework was mainly done by himself. At the time, Temmie was in school and was too busy with school work to draw sprites. Because of this, the concept art has a large amount of differences compared with the final version, as Toby could not draw some sprites, such as the bed, in a way he thought was acceptable.[26]
Concept art of the Lab reveals that a garage shutter door was meant to be in the wall area between Alphys's workstation and the entrance to the True Lab. It is likely that Mettaton was supposed to exit out of this door, since it is in the approximate area where he bursts out of the wall in the final game.
Clairvoire drew the bag of dog food.[27]
- If the protagonist calls Papyrus at the Lab's entrance, Sans appears in the call and alludes to Endogeny.[28]
- It is implied that the poster and the female human with cat ears figurine is of Mew Mew, a character from Alphys's favorite human TV anime, Mew Mew Kissy Cutie.[29][30]
- The poster and the heart poster shares the same design characteristics as Tokyo Mew Mew (also known as Mew Mew Power in North America), a magical girl romance anime.
- The comic involving a "giant robot fighting a beautiful alien princess" is referenced by Undyne on different occasions:
- In the Nintendo Switch version of Undertale, it is implied through Mad Mew Mew's dialogue that her body was originally found in the Lab.[35]
- The Xbox version confirms it through one of Mad Mew Mew's Dog Casino dialogue. Mad Mew Mew explains she had made Alphys faint while stealing the doll.
| Version tag | Changes |
|---|---|
| v1.001 | Several glitches were fixed or attempted to be fixed:
|
- ↑
...!? There's a camera hidden in the bushes.
— Narration for the Snowdin bushes near the Ruins - ↑
Actually, since you stepped out of the RUINS, I've, um...
— Alphys
... been "observing" your journey through my console. - ↑
(It's too dark to see near the walls.)
— Narration - ↑
I was originally going to stop you, but...
— Alphys
Watching someone on a screen really makes you root for them.
S-so, ahhh, now I want to help you!
Using my knowledge, I can easily guide you through Hotland! - ↑
(Yellow feet are tapping just behind the door.)
— Narration - ↑
ALPHYS updated status. just realized i didn't watch undyne fight the human v.v
— Alphys, UnderNet - ↑
ALPHYS posted a picture. CUte PIC OF ME RIGHT NOW ^.^
— Alphys, UnderNet - ↑
(It's a photo of a garbage can with several pink, glittery filters over it.)
— Narration - ↑
(O-oh n-no, is that another letter...?)
— Alphys
(I don't want to open it...) (C-can't I just slide it back out...?)
(...)
(N... no... I can't keep doing this.) (I'll read this one.) - ↑
ALPHYS AND I FINISHED OUR TRAINING EARLY.
— Papyrus
VERY EARLY.
SO I SENT HER HOME.
VERY HOME.
UH... NOW.
I FEEL STRONGLY AND FOR NO APPARENT REASON.
YOU SHOULD ALSO GO... THERE.
TO HER.
LAB... HOUSE. - ↑
Alphys told me that she would watch me fight you...
— Undyne, Genocide Route
And if anything went wrong, she would... evacuate everyone. - ↑
YOU'RE IN HER ROOM, UNINVITED? WOWIE...
— Papyrus, Cell Phone call on the Lab's the second floor
THAT'S EXTREMELY CREEPY. - ↑
(It's a video feed of your location.)
— Flavor text for the monitor - ↑
WAIT, THAT BAG OF DOG FOOD LOOKS FAMILIAR...
— Calling Papyrus a second time on the first floor
I REMEMBER SEEING IT... IN SANS'S ROOM?
YEAH! I ASKED HIM WHY HE HAD IT!
HE TOLD ME HE WAS TRYING TO EAT HEALTHIER. - ↑
(A garbage can.) (But it's pretty cute.)
— Flavor text for the trash can - ↑
OH-HO!!! THE PUZZLE THAT DR. ALPHYS MADE!
— Papyrus, Cell Phone call in the Snowdin Multicolor Tile Puzzle room
I HAD TO ASK UNDYNE TO ASK HER TO MAKE ONE. - ↑
ASGORE left me five messages today.
— ENTRY NUMBER 20, True Lab
four about everyone being angry
one about this cute teacup he found that looks like me - ↑
(It's just here to complete the look.)
— Narrator, inspecting the hole, Genocide Route - ↑
Ugh, ice cream!? Sugary... COLD... Talk about GROSS.
— Undyne, Cell Phone call in Waterfall's Nice Cream room
Now this chilly pink stuff that Alphys makes me...
THAT rules!!! - ↑
You have NO idea how many spears I wanted to throw!!!
— Undyne, Cell Phone call in the first room with sea grass
But, um, that seagrass is under scientific protection. - ↑
I told you that seaweed was like... scientifically important...
— Alphys
Really, I just... I just use it to make ice cream! - ↑
My friend helped me pick out this dress.
— Alphys
She's got a great sense of... - ↑
(There are letters from many monsters here...) (Froggit, Snowy, Doggo...)
— Narrator, inspecting the shelf
(They're all unopened.) - ↑
(An incredible invention.)
— Narrator, inspecting the bed
(When not in use, this bed folds into an extremely-easy-to-draw box.) - ↑
(It's a promo poster for Mettaton's TV premiere.)
— Narration for Mettaton poster
(On the flap it says "Thank you for making my dreams come true.") - ↑
By the time we reached Waterfall, Temmie was too busy with school to really do anything. So instead of spriting, I got her to sketch things and told her I would sprite over them instead. I’m not that good at spriting though. I couldn’t even draw the bed...
— Toby Fox, UNDERTALE Art Book, pg. 53 - ↑
resume: drew dogfood
— @clairvoire.bsky.social on Bluesky, September 20, 2025. - ↑
Papyrus: HMMM... A MYSTERIOUS SCIENCE HOUSE.
— Papyrus and Sans, Cell Phone call at Laboratory Entrance
Sans: the sign outside says "lab."
Papyrus: LAB?
Sans: like... laboratory.
Papyrus: LABRADOR... Y?
Papyrus: DOES THAT MEAN THERE ARE DOGS INSIDE?
Sans: i mean.
Sans: i wouldn't rule it out. - ↑
Uhh, hey, would you want to watch a human TV show together???
— Alphys
Sometime???
It's called, um, M...Mew Mew Kissy Cutie... - ↑
It's so good! It's um, my favorite show!
— Alphys, if "Sure!" is selected
It's all about this human girl named Mew Mew who has cat ears! - ↑
Alphys's history books made me think humans were cool...
— Undyne
... with their giant robots and flowery swordswomen. - ↑
I've READ Alphys's human history book collection!
— Undyne
I know all about your giant swords...
Your colossal, alien-fighting robots...
Your supernatural princesses... - ↑
GIGANTIC SWORDS!!! MAGICAL PRINCESSES! HERE I COME!!!
— Undyne - ↑
Do you think we can watch something with fighting next?
— Undyne, True Pacifist Route
Oh, and then... Something... With princesses!?
Or FIGHTING princesses!? - ↑
Wondering where I got this body?
— Mad Mew Mew in battle, Nintendo Switch version
WOULDN'T YOU LIKE TO KNOW!? HA HA HA HA!!!
Sure, I'll tell you.
I found it in... A strange place.
A... sciencey place.
No idea what was going on THERE, but...
As soon as I saw this body, I just knew --
IT WAS ME!!! ME!!! ME!!!!
So I TOOK it! You can't blame me!
Why does a scientist need a life-sized girl statue anyway!? - ↑
so far bugfixes include shrinking the hitbox of a bag of dog food
— @FwugRadiation on Twitter, January 10, 2016. [deleted] - ↑
@smellyfeetuhave well it's at least harder to do now (?) i couldn't figure out how to do it so its probably ok if its just a speedrun thing
— @FwugRadiation on Twitter, January 20, 2016. [deleted]