Neutral Route

For the ending in which Clover aborts the Pacifist Route by choosing to kill Ceroba at the end of her fight, see Pacifist Route § Flawed Pacifist Ending.

The Neutral Route is one of the three primary routes in Undertale Yellow, alongside Pacifist and Genocide. This route has Clover killing some but not all enemies. While the beginning plays out similar, if not identical to the Pacifist Route, the route begins to heavily deviate in the Steamworks. In this route, the final boss is Flowey.

Method

Like in Undertale, this ending occurs when the requirements for neither the Pacifist Route or a Genocide Route have been met. However, unlike Undertale, finishing this route is not a prerequisite for obtaining the Pacifist ending.

While Clover can make some different choices throughout, there is only one ending to the Neutral Route. However, killing bosses makes their corrupted variants appear in the final boss fight.

Differences

Dark Ruins

Dalv's dialogue is mostly identical to the Pacifist Route. The only major difference is that if Dalv is spared on a Neutral Route, he does not choose to pack up and move to Snowdin like he would in the Pacifist Route, but instead chooses to stay in the Dark Ruins and connect more with the residents.

If Dalv is killed, entering his room will allow Clover to play his Organ Demo. This is only available on the Neutral Route, as Clover will not turn it on during the Genocide Route.

Snowdin

Snowdin in the Neutral Route is identical to the Pacifist Route.

Dunes

El Bailador is not aware that Clover is fighting him unless they decide to kill him.

Ceroba's introduction dialogue is changed to be slightly less interested in Clover, as she can tell their SOUL is not pure.

If Starlo is spared, Clover can receive a letter from Starlo at the Steamworks - Commons UGPS station. After this point, backtracking to the Saloon in the Wild East unlocks a Neutral-exclusive scene. The Feisty Five, along with Ceroba and Dina, are celebrating the posse's reunion. Moray is performing a song on the stage. Mooch, Ed, and Starlo express their appreciation at seeing Clover again, while Ace and Ceroba do not want Clover to bother them.

If Clover kills Starlo during his fight, Ceroba will question where he has gone and will go to his family in hopes of finding an answer. If Clover enters Starlo's house up ahead, a Neutral-exclusive scene will play where Starlo's family will speculate as to where he could have gotten. Ceroba will leave the house without saying anything to Clover and his family worries about where he is. If Clover later backtracks to the Wild East, Mooch will be in front of the Feisty Five's house. She apologizes for ruining Clover's fun and expresses a desire to talk to Starlo about it. Ceroba and the rest of the Feisty Four cannot be found anywhere.

Steamworks

Guardener's body, if killed.

While much of the first section of the Steamworks is unchanged from Pacifist, the one major difference is that Ceroba does not follow Clover. This leaves Clover traversing through Steamworks alone with Flowey as their companion instead. Clover is able to access the UGPS stations while traversing through the Steamworks, as Ceroba prevents Clover from using them when following them on a Pacifist Route. This also allows them to backtrack to see the posse's reunion at the Wild East Saloon if Starlo was spared.

Once Axis first detains Clover, Flowey catches them at the bottom. They use the vent to escape right away; Clover does not build Daisy like in the Pacifist Route. In the Axis chase, they are not required to go in a locker like in the Pacifist Route. At the end of the chase cutscene, Flowey destroys Axis's arms by shooting a bullet at him in order to stop him from hurting Clover. The Guardener encounter plays out as usual. Her dialogue is slightly different from the Pacifist Route since Clover battles against her alone without Ceroba. If Guardener is killed, she assumes she deserves it. Her damaged body remains there for the rest of the route.

At the Crossroads, Clover heads upward into the Chemistry Lab since the Factory is not accessible without Ceroba. Clover is required to make a Steamworks ID to proceed. Vendy is far more polite if backtracking to them after obtaining the ID. Clover can also pick up the Cake in the Chemistry Lab, which is exclusive to this route, as Clover will not pick it up during the Genocide Route. Using the Hydrochloric Acid on the locked door will initiate a cutscene with Axis, who was standing right behind it. He has his own vial of acid that he intends to use on Clover. After struggling to open it, he drops and breaks the vial, burning a hole directly beneath him and causing him to fall.

At the Steamworks - Control Station UGPS sign, the Mail Whale descends and gives Clover Martlet's letter requesting to meet them on the roof of UG Apartments. In the room with the Furnace SAVE point, Flowey can be seen briefly disappearing behind Clover as they walk. This replaces Martlet's letter with the Missing Poster. At the SAVE point, Flowey will appear and offer Clover the Friendliness Pellets.

Once Axis's battery is fully drained, Clover can spare him by using the Compliment ACT 3 times to recover Axis. He apologizes for attacking them, explaining the lack of freedom all robots share. He expresses both envy of Clover being able to leave and optimism about the future of the Steamworks before granting Clover access to the Steamworks. Axis can later be found recharging next to his locker near the start of the Steamworks as an NPC and is happy to see Clover.

If Axis is killed, he calls out to Chujin Ketsukane for help before dying. His body remains there for the rest of the route.

Hotland

If Starlo was spared, Clover can pick up a letter from Ceroba at the Hotland - Crossroads UGPS sign.

Flowey stabbing Martlet.

Clover heads to the rooftop of UG Apartments to meet with Martlet. Flowey repeatedly interrupts them and tells them to turn around and head to Asgore Dreemurr, but Clover continues forward rather than waiting for the elevator. Martlet's dialogue here depends on how much LOVE Clover has, as well as if Clover aborted a Genocide Route in the Steamworks or not.

• Her overall dialogue differs with her being more sympathetic and kinder the lower their LOVE is and more skeptical and worried the higher their LOVE is. Martlet remarks that New Home is on the other side of the CORE in front of them. She talks about how she was told that all humans are the enemy. She mentions her plan to stop Clover if need be, but, although she hesitates on routes with higher LOVE, she throws away the vial of Determination. She tells Clover she knows they are good, but that ASGORE would kill them if they continued.
• If the Genocide Route has been aborted in Steamworks, regardless of Clover's LOVE, Martlet cuts straight to her being told humans are the enemy with a less cheery voice, as she now believes it is true. She still shows her vial and throws it away. However, she cannot bring herself to fight Clover, still sensing good in them. She challenges them to shoot her now, asserting they will never get past ASGORE, but Clover does not attack.

Either way, she offers for Clover to live with her, saying she can give them a peaceful childhood, as well as believing they can put the past behind them and change for the better at higher LOVE. Clover's options range from agreement to silence based on their LOVE, but they will not reject her offer. Martlet prepares to take Clover to Snowdin before swiftly being impaled by a vine sent by Flowey. Martlet assumes Clover stabbed her and questions their act (at lower LOVE) or says she should have known (at higher LOVE or Aborted Genocide in Steamworks) before dying. The screen fades into Flowey facing Clover, with his friendly persona dropped.

• On most variations, Flowey acts annoyed with Clover, knowing something like this would happen. If Clover never saved, he acts as if their friendship was one-sided. He taunts them about Martlet's death.
• If the Genocide Route was aborted in Steamworks, Flowey taunts Clover that he got to her first, then acts surprised that they were genuine about wanting to change. He tells them there is no redemption for their actions, but thanks them for turning it around anyway so they were not too strong.

Clover tries to initiate a battle with Flowey, but he loads over the SAVE to kill them first. He then absorbs Clover's SOUL, but Clover still holds on. He snaps at them about failing to reach ASGORE, and that they have always been predictable.

• If this is Clover's first Neutral Route, Flowey reveals that he has done hundreds of runs with Clover before. His goal was to get them to the five human SOULs, but Clover always stayed with Toriel if he did not interfere. In early runs, he manipulated them into leaving the Ruins, but they always died long before reaching ASGORE. Because of this, Flowey tampered with the switches in the Ruins to send Clover off-track into the Dark Ruins. After he is done expositing, he is irritated that Clover is still hanging on.
• If Clover has already completed a Neutral Route, he does not exposit.

He then starts his final boss fight.

His monologue at the end of the fight differs depending on how many times Clover has done the Neutral Route before.

• On their first run, Flowey calls them annoying for not giving in, though he admits he had fun for a moment. Flowey decides to reset the timeline back to when Clover first fell down. He says he may try this again if they end up in the same scenario, and advises them to make different choices if they can remember this, claiming there is a better timeline for both of them.
• On their second run, Flowey admits to having less fun than the first time. He initially talks to Clover as if they remember the resets, but stops, explaining that their lack of memory is why he says the same things every run. He talks about how they get through the Underground faster every run and holds out hope that this will eventually lead to something, but not for many resets.
• On their third run, Flowey expresses more desperation. He contemplates if it is even possible to keep Clover alive, as none of his hundreds of runs with them have amounted to anything. He considers that Clover may not be the human he needs.
• On their fourth run onwards, Flowey is annoyed with himself for leading Clover to the same place.
• On a run that is their fourth run onwards, as well as with Fun Value 70-80, Flowey expresses apprehension, believing he is able to feel another presence in Clover's mind. This hints at the player.

In every case, Flowey resets to perform another run with Clover.

Aborting

Aborting the Pacifist or Genocide Routes to enter a Neutral Route sometimes results in unique changes.

Pacifist Route

If Ceroba is with Clover during the Steamworks, a Neutral Route can still be entered by killing any enemy robot. Ceroba will still continue to accompany Clover throughout the Steamworks even if a robot was killed. However, after the battle with Axis, Ceroba does not go to Hotland and leaves Clover due to their soul being impure (with varying dialogue if Axis was killed or not). This changes some details of the regular Neutral and Pacifist Route progression afterwards.

• Because Ceroba is still present, much of the cutscenes and path throughout the Steamworks remain the same as in the Pacifist Route despite the route being aborted, such as going through the Factory instead of the Chemistry Lab, sparing Axis through Plan B instead of Compliment, and being unable to use UGPS stations until Ceroba leaves.
• Mail Whale delivers Martlet's letter right before the elevator to Hotland, rather than delivering it at the final Steamworks UGPS station. Flowey does not replace the letter with the Missing Poster when delivered this way.
• Neither Starlo's urgent letter (Pacifist) nor his update letter (Neutral) are sent.
  • The Feisty Five's reunion scene in the Wild East does not occur.
• Ceroba's Neutral Route letter is not sent.

Genocide Route

If a Genocide Route is aborted in the Dark Ruins by sparing Decibat by silence, then exhausting the Dark Ruins kill counter afterwards, Dalv has different dialogue during and after his fight.

Aborting a Genocide Route either by sparing Martlet after exhausting the Snowdin kill count or by failing the Dunes Genocide Route requirements brings a couple of changes.

• UGPS signs still cannot be used for the rest of the route.
• Martlet's dialogue when she reunites with Clover before Oasis Valley is more apprehensive.

The only way to abort the Genocide Route in the Steamworks is by failing to meet the kill count, which causes several large changes.

• Mail Whale delivers Martlet's letter just before the Hotland elevator and Flowey does not steal it, the same as in a Pacifist Route aborted in the Steamworks.
• Characters are still absent as if Clover had completed a Genocide Route, including Axis if he was spared.
• Martlet's speech on the rooftop is far less trusting.
• Ceroba’s corrupted variant appears in Flowey’s battle.

Trivia

• The elevator in UG Apartments remains in use and can never be ridden on a Neutral Route. This makes it the only route in the game where New Home is inaccessible.