20 Undertale Tips and Secrets

undertale guide tips and secrets
Undertale and Toby Fox: 20 Undertale Tips and Secrets

Amongst the thousands of RPGs, Undertale stands proud and tall amongst most others. From loving characters to addictive soundtracks, Undertale has everything many players are looking for in a game. Trying to get through the game, albeit fun, is rather lengthy and tricky without knowing these 20 tips and secrets.


1. Endings

One of Undertale’s most defining characteristics is its various endings. Throughout the player’s experience, the options they take will change the course of the gameplay, having vast consequences by the end of the game. The various routes are as follows:


Neutral Ending

This is the ending most players experience when playing for the first time. This route can be achieved by not killing nor befriending anyone. Because there are so many characters, this route is by far the easiest to obtain. If you decide to kill any monster– including non-bosses– the game will end in a neutral route, so long as you don’t go out of your way to kill everything. The neutral ending always ends in a phone call from sans (as you can’t kill sans unless doing genocide) in which he explains how the underground is doing after your influence. Killing certain characters will yield different results, as they do different things based on who is still alive. 


Additionally, the player must go through a Neutral route before being able to complete a True Pacifist ending. If the player completes a ‘Pacifist Neutral’ ending which occurs when the player doesn’t kill anyone but doesn’t befriend everyone, Flowey will appear at the very end and allow them to go back to their last save and befriend the rest of the people required for the True Pacifist route.


True Pacifist

The True Pacifist ending is by far the most wholesome and happiest of all the endings. It can be achieved after a Neutral route by sparing every monster and befriending all the bosses. Small note, the player is allowed to hit a monster say by accident, but if the monster dies as a result then the True Pacifist route will immediately be aborted, although the player can reload a SAVE to undo this.


Another key moment, after Undyne chases you into Hotlands, if the player leaves the room before giving them water, the route will also be aborted. After the True Lab, however, the True Pacifist ending cannot be aborted by means other than true reset. This ending allows the player to fight Asriel Dreemur and free the monsters from the underground, and also allows for some additional secrets to be accessed



The Genocide ending is often times considered the most difficult route to complete for more ways then one. For starters, you must be comfortable enough to endure every single death required, including scenes that purposefully guilt trip you for your actions. Additionally, the player must kill every monster, which doesn’t just include the ones encountered with: the player must actively seek out every remaining monster and kill them as leaving even one behind (except Jerry) can abort the route. 


For this reason, even if the player doesn’t catch to spare even some on their first run, unsuspecting players almost never obtain a genocide route. In order to ensure a genocide route, the player must be sure to exhaust the kill counter found when saving before reaching certain points. These kill counts are area-specific and vary depending on which part of the underground you are in. Note that the kill count for Hotlands and The Core are the same. 


Once the player defeats Mettaton NEO and the kill counter is completed, the genocide route cannot be aborted by means other then true resetting. After Mettaton, the player will have to fight sans– the last boss– and then talk to Chara to complete the ending. This interaction can lead to a secret 4th ending, but we’ll talk about that later.


2. Fun Value

Contrary to popular belief, ‘Fun Value’ has no correlation to how much fun is being had. The Fun Value is how the game sets itself up for various scenarios, such as the Wrong Number song and Alphys calling you in snowdin to order a pizza. The Fun Value is determined after resetting the game, and won’t change until another reset. There are other secrets related to this, but I’ll also be discussing later. 


3. Name Secrets

Upon starting the game, you are able to set a name for the player. When setting yourself to specific names, the game will return various responses. Here are some notable ones:


Alphys: “D-don’t do that.”

Asgore: “You cannot.”

Asriel: “...”

Flowey: “I already CHOSE that name.”

Sans: “nope.”

Toriel: “I think you should think of your own name, my child.”

Undyne: “Get your OWN name!”

Papyru: “I’LL ALLOW IT!!!!”

Frisk: *will activate hard mode*

Gaster: *will restart menu upon typing the last letter*


There are other names relating to other characters, all of which will allow you to use the name unlike most of these listed.


4. Step Counter

If you’ve ever played a Genocide run, you might find it increasingly more difficult to find monsters as you near the last few. You could walk around aimlessly hoping to cross paths with unlucky stragglers, or use this trick to increase your chances at finding those last few. If you move your character to an upper wall by holding your up arrow, then hold your down arrow simultaneously, your character will rapidly switch back and forth without actually moving. While this seems like an obscure visual glitch, what it’s actually doing is increasing your step counter.


Undertale determines monster interactions based on a system called a step counter. To put it simply, the more you move inside a room, the more likely you are to run into a monster. What this trick does is increase the amount of steps you gain per second, giving you encounters more often. This counter resets when you enter a new room, so be sure to stay in the same room when performing this technique


5. Pink Spare Names

In the Ruins, the player will run into a Froggit along the path who helps the player by describing the spare name mechanic. He explains that when a monster can be spared, their name will turn yellow. Promptly after telling you this, Froggit will ask you how useful this mechanic is. If you’re feeling feisty, you might be inclined to pick “No more Yellow Names,” in which he says he’ll tell all his friends to ‘throw out’ their yellow names. From this point on, the game will progress without yellow names, making it significantly more difficult to know when a monster can be spared.

Thankfully, this isn’t the end of the road. If the player comes back to that Froggit, they will ask how your game experience is going without the yellow names. If you choose to admit your wrongdoings and ask for the yellow names back, Froggit will share that everyone already threw out their names, but they should have pink ones still in their closet. From them, all the names will be pink as opposed to yellow when monstars are able to be spared.

One last easter egg, if the player asks Froggit to remove the yellow names, they can be found when investigating a pile of trash in the trash area of Waterfall.


6. Spider Donut

Tucked away on a detour in the Ruins, you might run into a couple of cobwebs labeled ‘spider bake sale,’ where they can purchase Spider Donuts and Spider Cider. The prices aren’t too hefty, being 7G and 18G respectively. While it might seem random, it is more than worth it to make one of these purchases. Later on in Hotland, you will encounter a boss named Muffet, a spider-human hybrid who leads the spider bake sale. Her fight is rather difficult, even introducing a new color heart, but by consuming a Spider Donut or Spider Cider, the fight will end immediately. This helps save a large portion of time especially when doing speedruns, so buying them is highly advised.

You may also notice that these items are sold right before the Muffet fight, so why am I suggesting to buy them in the Ruins? While it’s true they are sold there as well, they cost significantly more, costing an upwards of 9999G. Unless you’ve been grinding a lot or plain hacking, there’s not much chance you’ll just have that much lying around.


7. Punch Card Glitches

Multiple times throughout your gameplay, you’ll run into Nice Cream Guy, who surely will sell Nice Cream and Punch Cards for said ice cream. While seemingly simple, many Undertale speedrunners race to get their hands on Punch Cards, which certainly seems odd without reason. For context, there are a number of glitches that can be performed using Punch Cards such as Wrong Warps and moving while in dialogue, all of which will help shave time off a speedrun. There are a lot of factors that go into this glitch; so much so that it alone is deserving of an entire article. For now, we’ll pause here for the sake of time.


8. Dogaressa and Dogamy

Found in Snowdin, these two love dogs warm many players hearts with their puppy-like characters and undying love for each other. If you find yourself in a Genocide route, however, you’ll find that killing them may not be so heartwarming. Despite that, there’s a little secret to fighting them that may make your Genocide run a bit smoother. Since there are two of them, you will have to kill one at a time in order to get past them, but be careful who you pick. By killing Dogamy first, Dogaressa becomes intensely aggravated and will make her attack longer and more difficult than before. 

The same, however, cannot be said both ways. If you kill Dogaressa first, Dogamy will become so depressed that he loses all motivation to attack, making hardly any effort to hurt you. A truly sad fact that may even deter your route, but a secret nonetheless. 


9. Glyde

Tucked away in a corner of Snowdin, you might find yourself in a hallway with a locked door. Because of its short size, not many people spend much time here. Unbeknownst to many players, walking around in this room gives an encounter with a secret monster, Glyde. 

There’s not much to this monster other than the fact that it’s hard to find. Other than that, the fight is surprisingly normal. No new soul, no difference in music, but another monster to encounter nonetheless for those Undertale die-hards


10. Secret Room

Relating to the previous secret, you might grow curious on how to open this locked door. For those who’ve played a significant amount of the game, you might know that you can purchase a mysterious key from Bratty and Catty. This key, however, is for Nabstablook’s house, and not this door. So how do you open it? Well, it’s rather difficult. During the end of the True Pacifist ending, Asriel will come back and tell the player that they need to play through the special credits. Following this dialogue, words will appear from all over in synchronized orders that the player must attempt to dodge. There is no consequence for hitting one as it is stated the player has infinite health. But if you do happen to dodge every single one, the game will tell you “Incredible work. Somewhere, felt a door opening…!”

Upon going back to the save and returning to the door, the player will be able to enter. Inside, you will find a sleeping dog, a computer, puzzle, game, and another dog that crumbles to residue. This appears to be a reference to the creator of the game himself, Toby Fox.


11. Sans’ Room

While touring Papyrus’ house, you may notice the distracting door across from Papyrus' room highlighted with multi-colored fire underneath. When investigated, you’ll find that this room is also locked. Between the random fire and sans’ mysterious character, you might grow curious what his room would look like. Well, to get in, you first need to be in a True Pacifist route in Judgement Hall. After Sans judges you, quit the game and make sure you do NOT save beforehand. When you enter again, let sans judge you a second time. After his dialogue, he will say something new, pointing out that you have heard his spiel before and tell you a secret code.

Do not be tricked, because you will have to exit the game without saving for a second time. This time, Sans skips his dialogue and you tell him that you are a “stupid doodoo butt.” After this, Sans confesses that there is actually a secret secret codeword. After that, you will have to restart without saving one last time and go through his dialogue. This time, you tell him that you’re a “legendary fart master.” Sans will tell you that you’re wrong, and that it was actually his ‘secret secret triple-secret’ codeword before finally giving you a key you apparently already had.

After this point, you are safe to save and continue on your journey. If you go back to Papyrus’ house and go up to Sans’ door, you will enter a dark room where you seem to be walking endlessly. After a minute, Papyrus walks in and reveals that you’ve been walking on a treadmill in the dark. The rest of Sans’ room is rather unimpressive and humorous, just like Sans.


12. Gaster

Gaster is one of Undertale’s biggest secrets, with his character being made almost entirely out of pure fandom. But where does he actually appear? The answer is in a secret corridor past Sans’ post in Waterfall, although it’s not as easy as it sounds. Referring back to Undertale’s fun value system, Gaster can only appear with a fun value of 66. On top of that, he only has a 10% chance of spawning. So unless you’re incredibly lucky, there’s no way to find him without directly influencing the game’s code. To find him, simply enter the gray door that appears and you will see him alone in an empty room. Upon interaction, he makes a strange sound and disappears. Small note, it’s not actually confirmed that the ‘Mysterious Man’ inside this room is Gaster, although it is heavily 


13. Piano Room

Detoring from the main path in Waterfall, you might find a piano resting against a wall. A sign hanging on the wall adjacent reads “Only the first 8 are fine,” referring to the piano. Yes, the piano does unlock the door, but what notes are needed to unlock it? Further on, you’ll find a lonely statue sitting in the rain. If you give the statue an umbrella, which can be found farther down the path, a song will begin to play, followed by the musical translation appearing above it. When playing the first 8 notes of that song, the door will open.

Inside, you will find a red sphere labeled ‘Legendary Artifact’ on top of a lectern. If you try to take it, you will be told that you’re carrying too many dogs. Upon checking your inventory, an annoying dog will appear (and only in this room). It actually doesn’t matter how many spots are in your inventory, as the game will always tell you that you’re using too many dogs. If you use the dog, it will absorb the artifact and clip through the wall, never to be seen again.


14. Glad Dummy

In the trash section of Waterfall, you will encounter a dummy flowing with rage and eager to fight you in the name of the dummy you interacted with in the Ruins. It doesn’t matter what you did to that dummy, as the Mad Dummy will fight you regardless. However, if you are on a Genocide route, the Mad Dummy will actually turn into the Glad Dummy, skipping the fight. Do be warned that sparing this dummy does abort Genocide.


15. Thundersnail

One of the many peculiar interactions you’ll find in Undertale is an event called the ‘Thundersnail Race.’ Hosted by Nabstablook, you are offered to race other snails by cheering on your snail in the race for 10G. Despite best efforts, however, it may appear that winning the race is impossible. The good news is that there is actually a way to beat it. Pressing the cheer button 6-7 times at the start of the race periodically whenever the exclamation disappears will cause the snail to move at the optimal pace, giving you the win along with 9G, still leaving you net negative of 1G. However, if you repeat this process but stall the snail at the very end to cause it to lose, you will receive 30G as consultation. This process works indefinitely and is an efficient farm for the next tip.


16. Temmie Armor

At the end of the game, the player will receive a real knife and a heart locket. The stats are fairly high, so it’s reasonable to believe that they are the best pieces of equipment for endgame. Surprisingly, this is not true. The best piece of armor is actually the Temmie armor, purchased at Temmie’s shop from 750G to 9999G. Before you can buy it, first you will have to pay for Temmie’s college, which will cost upwards of 1000G. After that, the armor will be available to purchase, in which the price decreases after every death up to the 25th. The deaths counted persist among resets AFTER the true reset (Genocide reset), but do not account for Game Over’s that don’t result in death (Papyrus’ fight). The armor’s cost is certainly worth it, however, as the armor not only has 20 defense, but heals every other turn, increases your i-frames, AND adds 10 to your attack. Do note that this armor is inacessible in Genocide, so you will have to rely on the heart locket and pure skill.


17. So Sorry!

In case you just couldn’t get enough of Undertale’s fights, then this is the tip for you. There is actually a secret fight that can only be accessed on the 10th of October, 8PM. In Hotlands, above a T cross section, a secret glass path will reveal a room covered with cacti and a sign for the art club. If you wait for that time of year (or just change your computer’s time settings), the boss will appear and run into you, instigating a fight. There isn’t much canon tied with the character, but nonetheless a fun hidden mini boss.


18. Mettaton’s Prompt

When fighting Mettaton, a small break will occur where they ask you to type into a box. Most of their responses vary depending on the amount of characters put in. For instance, by writing nothing, Mettaton states that you are speechless. By writing 1 letter, they tell you that you are concise. Generally, the more characters you put, the more ratings you receive. However, there are certain essay submission that will elicit unique responses from Mettaton:


Arms - “How creative. Arms… most people just think about my legs.” +250 Writing

Dancing - “Dancing…? Thank you, I’m self-taught.” +250 Writing

Hair - “My hair… yes, I use metal hair gel.” +250 Writing

I love you - “What a touching confession! I’ll add it to the pile.” +250 Writing

Legs - “That’s right. Legs was the correct answer!” +350 Writing

Personality - “Yes, my personality is quite charming, isn’t it?” +250 Writing

Toby - “Toby? What the hell is that? Sounds… sexy.” +300 Writing

Voice - “They say I have the voice of a siren…” +250 Writing


19. Toriel’s Pie

When fighting Asgore, you might die many times depending on how well versed you’ve become to the game. This isn’t abnormal as Asgore is meant to be a difficult boss. However, there is a way to make his fight easier. If you’ve managed to hold onto Toriel’s pie since the beginning of the game and eat it during Asgore’s fight, he’ll recognize the pie, decreasing his attack and defense. Additionally, you can eat the pie when trying to save Toriel and Asgore’s souls in the Asriel fight to more effectively save them.


20. Chara

At the end of a Genocide route, you will encounter a small child similar in appearance to Frisk and goes by the name “Chara.” The entire interaction is scary to say the least, and by the end of it, they offer to erase the entire world to complete their mission. By agreeing, the game turns into an empty black void and closes, leaving nothing left to offer. If you tell them not to, they tell you that you aren’t in control and jumpscare you, shaking your screen when windowed. Either way, the game practically deletes itself, but not all hope is lost.

When opening the game again and waiting a bit, Chara talks to you again, asking why you’ve come back. They offer to do a True Reset for your soul, which would allow you to play the game normally again. There is a miniscule difference, however, and this is where the secret 4th ending comes in. Upon completing a True Pacifist following a Genocide, at the very end, the ‘The End’ card is replaced with a reminder of your dark past, dubbed the ‘Souless Pacifist.’ 

Likewise, if the player decides to stay with Toriel, the bed scene is also slightly altered.

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Just a traveling author, going from place to place looking for the next stage to find my audience. Next stop, gaming articles!
Gamer Since: 2012
Favorite Genre: RPG
Currently Playing: Minecraft
Top 3 Favorite Games:Undertale, Five Nights at Freddys, Metal Gear Rising: Revengeance

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