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Si re, si re si mi si mi

Shyren, after humming once

Shyren (/ˈʃaɪrən/) is an enemy that appears in Waterfall.



Shyren is a fish-like monster, ashamed of her scary face and poor singing abilities. She fights with her back turned to the protagonist. Her "body" is a separate entity from her while her "head" is her entire body.


She is insecure, and ashamed of herself, and her song. The protagonist may help her feel more comfortable singing. Shyren is implied to enjoy performing in general, as Undyne had once taught her piano lessons.[1]

Main Story

Shyren had originally relied on her sister speaking in her stead until her sister went missing. She shortly after became a recluse. Shyren was previously friends with Mettaton and Napstablook, and liked the notion of performing with them.[2]

True Pacifist Route

Lemon Bread and Shyren screenshot.png

In the Epilogue, Shyren is reunited with her missing sister, who turned into an Amalgamate. In the ending credits sequence, she joins Mettaton, Napstablook and Burgerpants on tour as Mettaton's back-up singer.

In Battle


  • Shyren attacks with music notes from her head. These get faster and more ample every time she is hummed to.


  • To spare Shyren, she must be Hummed to at least once.


  • .... .... toot .... [Neutral]
  • Si re, si re si mi si mi [Hum #1]
  • Si Fa Si Fa So Fa So Mi Re Re [Hum #2]
  • Mi So Mi So Mi Si Mi La Si So [Hum #3]
  • (aggressive tooting) [Hum #4]
  • (final toot) [Hum #5]

Flavor Text

  • Tone deaf. She's too ashamed to sing her deadly song. [Check]
  • Shyren hides in the corner but somehow encounters you anyway. [Encounter]
  • A talented singer, with a little help. [Check after humming once]
  • That's Shyren. She's your band-mate. [Check after humming a few times]
  • Smells like music. [Neutral]
  • Shyren thinks about doing karaoke by herself. [Neutral]
  • Shyren hums very faintly. [Neutral]
  • Shyren taps a little beat with her fins. [Neutral]
  • Shyren pretends to be a pop idol. [Neutral]
  • You wave your arms wildly. You are now vulnerable to electric attacks. [Conduct]
  • You wave your arms wildly. The crowd eats it up. [Conduct after humming a few times.]
  • You smile. You ask to see Shyren's smile, too. Shyren gets quieter. In the corner, Aaron nods his head approvingly. [Smile without humming / After humming only one time]
  • You keep smiling. But nothing happened. [Smile #2]
  • You give a darling smile and a little wink. The crowd goes wild! [Smile after humming a few times]
  • You hum a funky tune/sad song/jazz ballad. Shyren follows your melody. [Hum #1]
  • Shyren seems much more comfortable singing along. [After humming once]
  • You hum some more. Monsters are drawn to the music. Suddenly, it's a concert... [Hum #2]
  • Sans is selling tickets made of toilet paper. [After humming twice]
  • A hooded figure watches the commotion from afar. [After humming twice, if Papyrus had been killed]
  • You hum some more. The seats are sold out. You feel like a rock star. [Hum #3]
  • The crowd tosses clothing. It's a storm of socks. [After humming thrice]
  • You hum some more. But the constant attention... The tours... The groupies... It's all... [Hum #4]
  • Shyren thinks about her future. [After humming four times]
  • You and Shyren have come so far, but it's time. You both have your own journeys to embark on. You hum a farewell song. [Hum #5]
  • Shyren's voice gets raspy. [Low HP]


  • Shyren's name is a combination of shy and siren.
  • Shyren is always encountered, even if the kill counter in the area is depleted.
  • Shyren is only the small fish atop the apparent body, which in turn is her talent agent.
  • Shyren sometimes utters the phrase "Si-Re Si-Re, Si-Mi Si-Mi" during battle, which may be a reference to "Si-Re Si-Mi" by Franco Godi.
  • The words that Shyren says seem to be the solfège scale from re to si. Although sol is usually spelled with an "l", Shyren uses the variant two-letter spelling; this may be to keep the two-letter sequence going.
  • If Shyren is hummed to 5 times, Knight Knight can be put to sleep one turn earlier than normal, mentioning that "You sing Shyren's song".
  • Undyne also wonders about Shyren's song.[3]
  • Shyren is one of the monster species making up the Amalgamate Lemon Bread; specifically, Lemon Bread is spared by humming, an ACT adopted specifically from Shyren, and Lemon Bread appears to have Shyren's agent as her main body, giving her a similar overall figure to Shyren's.
  • Shyren's yellow text in the True Pacifist Ending Credits, "Released Her First Single 'When You Say Goodbye It's Like Magical Bullets Are Slowly Flying Out Of Your Mouth And Hitting Me' " is a joke of the way Shyren attacks the protagonist.


  1. Oh yeah, Shyren lives around here. I used to give her piano lessons. She was really talented... for someone with no fingers. One day, she stopped coming to her lessons, though... - Undyne
  2. Shyren's sister "fell down" recently. It's sad. Without her sister to speak for her... She's become more reclusive than ever. So I reached out to her, and told her... That she, Blooky, and I should all perform together sometime. She seemed to like that idea. - Napstablook's Cousin's diary.
  3. How did her song go again...? - Undyne