Blue
As Mr. Butterfly says, Flowers be not weapons of war.
Blue, Chapter 5
Blue (JP: ブルー) is one of the 7 Colored Flowers in Chapter 5 of Deltarune. He is the representation of the blue flower that was part of Asgore and Toriel's wedding bouquet.
Blue's associated trait is integrity.[2] He is based on the Integrity SOUL from Undertale, wearing ballet shoes and a tutu.
Blue is a humanoid plant with dark blue skin and light blue hair, making him the only one of the flowers with hair lighter than his skin. He has dense hair worn in a ponytail, as well as prominent eyebrows. He almost always has his eyes closed, only opening them for certain rare expressions. His attire consists of a light blue bodystocking, a tutu skirt that resembles flower petals, and a pair of pointe shoes.
He sometimes appears with blue, simplistic butterfly wings coming from his back, able to fly through the air. He can do this effortlessly, even while carrying Yellow.
"Mr. Butterfly" appears in dialogue as an extremely realistic, animated butterfly, with simple faces appearing on its wings to express emotions.
Blue presents himself in a feminine manner, as he is dressed in traditional female ballerina attire and refers to other people, especially Yellow, as "dear". He generally behaves elegantly, speaking in poetic ways and restraining his emotions. Blue's main passion is love in all forms, although he also expresses himself through dancing on stage to various forms of music, and, after a rocky start due to the party's issues with Yellow, he strikes a cordial relationship with them, not truly wanting to be opposed to party due to both sides of the conflict being driven by love in one form or another. He does not hold a grudge against the party when he finds out about their interactions with Yellow, caring more about their honesty.
He seems somewhat passive towards violence as a means of problem solving, assisting Flowery's plans despite having some qualms, and engaging in battle alongside Yellow against the party to force them to prove their innocence.
Blue also dislikes characters getting hurt, due to it opposing his style of putting on a show. Hence, he would do whatever he can to heal to max, remarking that it is a comedy, not a tragedy.
Despite embodying and valuing the virtue of integrity, Blue shows himself to be somewhat lacking in it, evading a $2 debt to Green by pretending to not comprehend their requests, and stealing from both Yellow and Orange in order to make them gifts, even deciding to not return Orange's gloves to her after she expresses dissatisfaction with the gift made from them.
He appears to be one of the more perceptive and intelligent flowers, commenting on the relationships the characters have with each other, such as Susie's deep love for Noelle. He often provides support and comfort to Yellow, which Yellow often needs, due to his naive behavior and quickness to despair. For example, when he finds Yellow in a self-imposed imprisonment, he releases him, hugs him, and reassures him.
He sometimes projects his emotions onto a butterfly rhetorically, which he refers to as "Mr. Butterfly".
Blue is one of the 7 Colored Flowers that made up Asgore's wedding bouquet, initially grown as a proposal to Toriel that was only meant to last one day. Instead, Asgore continued to take care of them for years, keeping them alive in glass containers until the present day, and talking to them as friends. At the start of the game, the flowers are kept in the back room of Flower King.
Blue is first alluded to by Miss Mizzle during very specific ACT dialogue. She calls him a disciple of her speech and speaks highly of him, describing him as "a specimen of elegance and kindness."[3]
At the Ideal Diner in the Garden, Yellow mentions Blue during a conversation.
In the Cliffs, Blue is mentioned by Seth during a conversation with Aqua, when Aqua questions why her name is "Aqua" and not "Blue". Later in the area, Yellow can be found looking for "blue grasses", an apparent misunderstanding of Blue's desire to hear bluegrass music.

Blue first appears in person in his room in the eastern wing of Flower Castle, where he approaches the party as a friend, explaining that as a messenger of love, he cannot stand against people whose actions are driven by it. Despite being ordered to stop them by Flowery, he offers to give his key and his blessing to the party in their efforts, only to stop when Yellow fails to arrive for the ceremony. Sensing that something is amiss, he proceeds to investigate the aftermath of the party's earlier encounter with Yellow, finding evidence of a struggle before learning from Aqua that Yellow jailed himself after trying to blow himself up.
Upon freeing Yellow from jail, he informs him that the heroes are the ones who convinced him he needed to be punished, prompting Blue to start their shared battle. During this battle, he still helps the party by providing them evidence they failed to collect earlier when acted on. Blue is also revealed to be the culprit behind the final crime, having stolen a bunch of Yellow's special petals, a reveal that ends the battle as Yellow does not want to embody justice anymore if it means he has to arrest Blue. Blue then explains that he stole the flowers to make a blue-and-yellow bouquet as a gift for Yellow of his own, causing Yellow to leave happily and convincing him to give the party the key on the condition that they do not trick Yellow again. Later in the east side, he approaches Susie to offer advice on what type of flowers would best symbolize her love for Noelle.
Later, at Top of Castle, Blue joins the other flowers in their efforts to stop the party's advance, though he also creates platforms for them to stand on. When they successfully pass through his and Yellow's shared section, he assures Yellow he did great before embracing him and flying off. They both reappear during the fourth phase of Flowery's battle, providing backup.
In the aftermath of Kris's final showdown with Flowery, Blue fully heals them both, stating that this story is a comedy, not a tragedy. Shortly after, he returns to his true form and thanks Kris for watching the flowers' dream.
After the Dark Fountain is sealed, Susie has Blue share his container with Yellow so she can replace Flowery's broken one, reflecting the love the two had for each other in the Dark World.
1. Flower Track
Blue will make what can be assumed to be vines to loosely follow the SOUL whilst spawning a flower in a 1 second interval, these flowers will explode into 8 projectiles after 1 second of being active, each petal determining where these bullets will go. Yellow will shoot out a bullet to follow the path that Blue has made.
Evidence
Gather more Evidence./All evidence gathered.
- Yellow brings the gun's![sic] Blue brings the elegance! [Encounter]
- A dancer who believes love to be integral to life. [Check]
- Smells like flowers. [Neutral]
- You feel a strange lack of EVIDENCE.
- The trial is ready! Use Yellow's JUSTICE act to begin! [40% TP]
- You began the trial! [Justice]
- Seth glances nervously at books...
- Green conspiciously[sic] oils the popcorn pan...
- Aqua laughs obviously about how red her ribbon is.
- Blue looks wistfully at the string and sighs.
- (Felt as if the evidence was correct...) [Correct evidence]
- (Felt as if the perpetrator was correct...) [Correct accusation]
- (Felt as if you weren't close at all...) [Neither correct]
- You used the Annoying Dog!
- It was deployed like an off-brand missile!
- BLUE cast HEALING RAIN on YELLOW!
- Blue posing with butterfly wings
- Blue opening one eye
- Blue throwing open the entrance to Yellow's prison cell
- Blue embracing Yellow
- Blue in a dramatically sad pose
- Blue hovering with butterfly wings
- Blue with his eyes open, looking stern or suspicious
- Blue with his eyes closed, looking sad
- Blue with his eyes open, smirking
- Mr. Butterfly blushing
- Mr. Butterfly angry, with a face both on his head and wings
- Blue moved in the same jar as Yellow, after Susie and Kris put the former's over Flowery
- Unused animation of Blue walking with Yellow
- Unused animation of Blue walking with Yellow to the right
- Unused animation of Blue patting Yellow's head
- Unused animation of angry Mr. Butterfly
- When using Susie or Ralsei's HelpOut ACT in battle, they will dress up as characters from the Ace Attorney series.
- Susie will be dressed as detective Gumshoe, Kris as Miles Edgeworth or Franziska von Karma, and Ralsei as Trucy Wright or Maya Fey.
- The relationship between Blue and Yellow might be a nod to a play M. Butterfly by David Henry Hwang.
- If the player attempts to attack Blue, Yellow blocks the attacks directed at him. This makes it impossible to damage Blue.
- Out of the six color flowers, Blue is the only one with a proper face sprite for his dialogue.
- Unlike Flowery's face sprite, which shows him with colored eyes on the rare occasions he opens them, Blue's face sprite is entirely monochromatic like those belonging to Lightners.
- Blue's battle animation appears to be visually inconsistent with the legs. The leg on which he is standing switches from the left leg to the right leg as he spins, and when the animation loops, the legs snap forwards, switching again.
- ↑ The game prioritizes giving out unowned evidence in this order: 1) evidence needed for the upcoming trial, 2) evidence not needed for any trial, 3) evidence needed for a different trial. The order of evidence is randomly shuffled within each of these categories. This guarantees using this ACT always grants the necessary evidence for the next trial (unless it is already owned). This ACT only grants one evidence if there is only one unowned.
- ↑
... w-wait. Does that mean, I'm stealin' smiles, from Blue?
— Yellow, Chapter 5
Oh no... I couldn't face him knowing I did that...
Wait! I know! I'll just get him a hunder'd million grasses. Then it's all even. - ↑
A dancer who believes love to be integral to life.
— Blue's Check dialogue, Chapter 5 - ↑
The Bluest Flower, A disciple of my speech
— Miss Mizzle, ACT dialogue, Chapter 4
Shy to no camera, And a specimen of
Elegance and kindness.
Should you meet, Please give my regards. - ↑ gml_object_obj_yellow_enemy_create_0 script, lines 74–183, Chapter 5