This isn't a full sequel but more covers a span of time the original oneshot neglected to show for the sake of keeping the oneshot on the shorter side.

Error shifts slightly in his space themed dress, narrowly glaring at Nightmare.

"WhY dId I lEt YoU tAlK mE iNtO tHiS? tHiS iS mY vAcAtIoN, aNd HeRe I aM, sInGiNg To An AuDiEnCe Of PeOpLe." Nightmare rolls his eyelights, shrugging.

"C'mon, it's almost time for us to Duet together." Error blinks, rage slowly vibrating his body.

"WaS tHaT a PuN?!" Nightmare shakes his head.

"Just read the lyrics on the karaoke screen and sing, okay?" Error huffs, slowly nodding.

"FiNe." Nightmare nods, leading the two up onto the stage, fixing his soft lavender dress.

"Go ahead and lead, Era." Error rolls his eyes at the nickname.

"FiNe, NiGhTlIgHt." Error takes a deep breath in, stepping up to the mic. Error's eyelights drift to the screen, hesitantly singing.

"ThE qUiEt TrEeS aRoUnD yOu StArT tO sHaKe, RuMbLiNgS fRoM tHe EaRtH, sEcReTs AnD sHaDoWs ThReAt To WaKe!" Error closes his eye sockets, slowly getting comfortable, "WhAt LuRkS bEyOnD tHe DaRkNeSs, StEpS iNtO tHe LiGhT, aNd NoW yOu'Re TrApPeD hErE, aLl AlOnE nOwHeRe To HiDe."

Ink steps into the AU's club, momentarily relaxing as he hears an unfamiliar and yet so very familiar voice singing softly.

"All that's familiar to you suddenly feels strange, The calm and steady now marked with scars you can't explain." Nightmare's voice, a tenor voice full of dulcet tones, rises to match Error's baritone voice. "The friendly faces now faded into foes, It went unnoticed, now it's all you seemed to know."

Ink closes his eye sockets, leaning on a wall and listening to the music.

"OnE bReAtH, tHe WoRlD tUrNeD bAcKwArDs, TwO bLiNkS, nOtHiNg'S tHe SaMe," Error begins to use his magic, his strings emanating with love, protection, and an unknown melancholy. "MeMoRiEs ArE fRaYeD aNd FrAcTuReD, cAn YoU hOlD tO wHaT rEmAiNs?"

Ink opens his sockets, blinking when he sees the strings moving through the air, coming from a skeleton both unfamiliar and familiar.

"That is Era, and Nightlight. They're both newcomers, but they sing well and draw a crowd like n'er before, so we let em do whatever." Ink vaguely pays attention to the barstaff's words, focused on what his enemy and an unknown skeleton that looks like a lavender Dream are doing on stage.

"The hunt becomes the hunted, Haunted days, and sleepless eyes," Nightlight smiles softly, twirling, a purple silken scarf coming from an unknown location, "What you knew, cannot be trusted. Buried truths uproot tonight!"

Ink narrows his gaze, but relaxes for the time being, listening to the lyrics of the song.

"AnD yOu'Ll BeNd AnD yOu'Ll BrEaK, aNd YoU'lL bUrN, aS tHe GrOuNd, ClAwS yA dOwN, tO tHe DiRt- HiD aWaY fRoM tHe LiGhT oF tHe MoOn-" Error's arms fold, vaguely resembling a hug if the person doing said hug didn't know what a hug was.

And that's when Ink hears something he's never heard before as Error and Nightmare begin to sing together.

"GoTtA fIgHt, GoTtA tRy, To SuRvIvE, pLaNt YoUr FeEt, FaCe ThE bEaSt, StAy AlIvE." The two voices blend together in a soft harmony, "AlL aT oNcE, aLl ThE cHaOs Is LoOsE, aS wE gRoW oVeR sHiFtInG rOoTs."

"YoUr HiSt'Ry CrAcKs AnD cRuMbLeS lIkE sToNeS bEnEaTh ThE sEa!" The two continue to sing together for a few moments, Ink's gaze resting on how they both seem relaxed, at peace, and enjoying themselves.

"No time for falls or fumbles, Must go, and take the leap!" Nightlight twirls, leaning off the stage as if he'll jump, pulled back by Error's strings.

"MoVe QuIcK, dOn'T lOsE yOuR bAlAnCe. CaN't SwAy Or LoOk BeHiNd." Error is far quieter than his chiper young friend.

"BeLoW cReEpS gReEd AnD mAlIcE, yOu CaNnOt StOp YoUr ClImB!" The two join in harmony again, Error stepping back momentarily.

"And you'll love, and you'll lose, and you'll learn," Nightlight smiles gently, "While your prayers and despairs go unanswered." A sad melancholy echoes in the smile, "Though you try, not all blossoms bear fruit." And that's when Ink figured it out.

Nightlight is Nightmare, Dream's twin brother.

Error chose this moment to come back into the pitcture.

"GoTtA hOlD, aNd CoNtRoL, tHe UnKnOwN." Error's baritone voice echoes with strength, "sTaNd Up HiGh, ThOuGh YoU mIgHt Be AlOnE. gO aFrAiD," His strings begin curling back around himself like a cocoon, "fAcE tHe TeRrOrS aNd ChOoSe," Error smiles as he sings "WiLl YoU bE rEaDy FoR sHiFtInG tRuThS?"

Will you be ready for shifting truths?

Ink frowns.

Shifting truths?

"EvErYbOdY's GoT a SeCrEt To HiDe," Yet again with the harmonization, "KeEp It ClOsE iT lOcKeD iNsIdE," If Ink didn't know better, he'd think these two are actually friends, "bUt ThOuGh ThEy TrY, iT wIlL fInD tHe LiGhT" But the raw emotion these two are singing with, "sOmEtHiNg LuRkS, sOmEtHiNg CoMiNg To LiFe." And the way they seem so comfortable with each other...

"YoU fEeL tHe GrOuNd As It HeAvEs AnD bReAtHeS." Ink's solid thinking no longer seems so solid, "sOmEtHiNg'S sHaKiNg MaKiNg HiStOrY." Ink narrows his gaze at the two on the stage, "rIsE fRoM tHe BoTtOm, RiSe Up FrOm ThE tRuTh." Acting like they didn't want to destroy the whole multiverse, "EvErYtHiNg TiEd To ThE sHiFtInG rOoTs!" Acting like they are relaxing for the first time in a long time.

"AnD yOu'Ll BeNd AnD yOu'Ll BrEaK, aNd YoU'lL bUrN," Error scratches at a scar on his ulna absentmindedly, Nightmare gently swatting his hand away from the scar.

"And you'll love, and you'll lose, and you'll learn," Nightmare smiles gently, the lavender silk covering his face ever so slightly.

"YoU'rE gEtTiNg ClOsE nOw! SoOn YoU'lL kNoW hOw" The two begin dancing around each other, huge smiles on their faces as they continue to sing.

"HoW tO fIgHt, AnD sUrViVe ThRoUgH tHe NiGhT," Error picks Nightmare up bridal style, the two smiling, barely containing laughter.

"Stand up high, face the beast, stay alive!" Nightmare holds the silk up above his face, a sorrowful look crossing for just a moment.

"YoU cAn MaKe It ThRoUgH, hOlD oN tO yOuR sHiFtInG rOoTs." Error joining Nightmare breaks the latter out of his sorrow, a smile gracing both faces again.

"GoTtA hOlD, aNd CoNtRoL tHe UnKnOwN." Error's strings wrap around both gods, tightening slightly.

"Show the world that you're eager to grow!" Nightmare seems unconcerned by the strings, resting his forehead on Error's.

"StArE dOwN tHe UnMoViNg TrUtH, bY fAcInG yOuR sHiFtInG rOoTs," The music ends, the two separating with care and dashing backstage.

Ink doesn't notice, swimming in a sea of thoughts as Dream arrives.

"Ink! Another Underswap fell!" Ink looks at Dream, nodding slightly.

"Right. I'm on it."

(1078 words.

Thank Catalyst on Discord for suggesting a part two.

The song is "Shifting Roots" by Blixemi (Linked in Media above)

Hope you enjoyed.