UNDERTALE 10th Anniversary events
Numerous UNDERTALE 10th Anniversary events occurred in 2025 through 2026 to celebrate Undertale's Anniversary, with some content also dedicated to Deltarune. This includes teased content from the FALL 2025 issue of the Newsletter, albums, merchandise, and concerts.
The 10th Anniversary Stream was a 2-day charity stream and the main event. It is a playthrough of a modified version of Undertale exclusively for the stream, and with live commentary from Toby Fox, and the three "Fangamer Dads" as hosts. It also featured intermissions, with fan submitted memories, live action skits, and Fangamer staff contributing to scene changes for the Ruins-themed room.
For Deltarune, it has certain characters cameoing, or their Undertale counterpart appearing. It has its own soundtrack, with guest contributors such as Carlos "insaneintherain" Eiene, Marcy Nabors, and Camellia.
The UNDERTALE 10th Anniversary Concert is a currently-ongoing live concert that tours exclusively in Japan, and is performed by MUSIC Engine, who also performed the UNDERTALE 5th Anniversary concert.[2][3] The touring began on September 13, 2025, and had special performances: with Sendai Philharmonic Orchestra on December 27, 2025, and a special Valentines program on February 14, 2026. The final performance is scheduled for May 2026.
The 2026 encore performances also includes Carlos Eiene's Song that Plays when Somebody Verses sans., which originated from the UNDERTALE 10th Anniversary Stream and the website-exclusive 10th Anniversary battle versus Sans.
The April 2026 and onward performances for "Program C" are scheduled to also not feature Battle Against a True Hero, Power of "NEO", or MEGALOVANIA, and has selective tracks tailored in homage to Undertale's slogan.[4]
The UNDERTALE The Determination Symphony is an upcoming world tour that spans from August 23, 2026 through February 28, 2027.[5] It is being produced by Lambert Jackson Productions, who originally ran the one-day Undertale – 10th Anniversary Orchestral Concert on June 22, 2025.[6]
It will be played by a 25-piece orchestra, and is intended to feature a large screen above the orchestra, depicting gameplay during the concert. It currently has a newsletter, with planned merchandise.
Includes collaborations such as albums and other merchandise.
Monstercat x Undertale, also known as UNDERTALE (10-Year Anniversary Remixes), is a remix album by various Monstercat and Firaga artists, consisting of remixes of tracks from the UNDERTALE Soundtrack. It was released on October 6, 2025.[7]
The album was first announced on September 12, 2025, alongside a unique animation.[8] In preparation for the album's release, the tracks sans. (Tokyo Machine Remix) and Death By Glamour (VGR Remix) were released early as singles on September 22, 2025 and September 29, 2025 respectively.[9][10]
| No. | Title | Length | Author |
|---|---|---|---|
| 1 | Fallen Down (Øneheart Remix) | 2:03 | Øneheart |
| 2 | Once Upon a Time (No Mana Remix) | 4:15 | No Mana |
| 3 | sans. (Tokyo Machine Remix) | 2:40 | Tokyo Machine |
| 4 | Ghost Fight (RoboRob Remix) | 2:38 | RoboRob |
| 5 | Spider Dance (Vector U Remix) | 3:15 | Vector U |
| 6 | CORE (RoBKTA Remix) | 3:33 | RoBKTA |
| 7 | Death By Glamour (VGR Remix) | 3:15 | VGR |
| 8 | ASGORE (PrototypeRaptor Remix) | 3:37 | PrototypeRaptor |
| 9 | Hopes And Dreams (Haywyre Remix) | 3:38 | Haywyre |
| 10 | MEGALOVANIA (Pegboard Nerds Remix) | 2:50 | Pegboard Nerds |
UNDERTALE x SQUARE ENIX is a merchandise and music collaboration between Undertale and SQUARE ENIX. Two music albums, as well as five T-shirt designs were produced.
T-shirts produced for the collaboration included designs of Sans and Chocobo from the Final Fantasy series, the protagonist and Tonberry, also from Final Fantasy, as well as Annoying Dog and Emil from the NieR series. Additionally, two T-shirts with the covers from the collaboration's two albums were also released. All T-shirts were released on March 18, 2026.
UNDERTALE: CHITEI DE CHILL is the first album produced for the collaboration, released on January 28, 2026 as part of SQUARE ENIX's Chill Arrangement series.
| No. | Title | Length | Author |
|---|---|---|---|
| 1 | Once Upon a Time (Remixed by grooveman Spot) | 3:11 | grooveman Spot |
| 2 | Fallen Down (Remixed by DJ Mitsu the Beats) | 3:27 | DJ Mitsu the Beats |
| 3 | Another Medium (Remixed by grooveman Spot) | 3:52 | grooveman Spot |
| 4 | Enemy Approaching (Remixed by DJ Mitsu the Beats) | 3:32 | DJ Mitsu the Beats |
| 5 | Nyeh Heh Heh! (Remixed by DJ JIN) | 2:57 | DJ JIN |
| 6 | Spear of Justice (Remixed by GORO KUMAI) | 3:31 | GORO KUMAI |
| 7 | It's Showtime! (Remixed by G.RINA) | 2:52 | G.RINA |
| 8 | It's Raining Somewhere Else (Remixed by DJ HASEBE) | 3:12 | DJ HASEBE |
| 9 | MEGALOVANIA (Remixed by VaVa) | 2:52 | VaVa |
| 10 | Ruins (Remixed by MURO) | 3:46 | MURO |
| 11 | Spider Dance (Remixed by GORO KUMAI) | 3:11 | GORO KUMAI |
| 12 | Uwa!! So Temperate♫ (Remixed by doooo) | 3:08 | doooo |
| 13 | Temmie Village (Remixed by MURO) | 2:48 | MURO |
| 14 | Home (Remixed by doooo) | 2:42 | doooo |
| 15 | ASGORE (Remixed by DJ Mitsu the Beats) | 4:19 | DJ Mitsu the Beats |
| 16 | Snowdin Town (Remixed by VaVa) | 2:53 | VaVa |
| 17 | Oh! One True Love (Remixed by DJ HASEBE) | 3:09 | DJ HASEBE |
| 18 | Alphys (Remixed by G.RINA) | 2:42 | G.RINA |
| 19 | His Theme (Remixed by DJ JIN) | 3:53 | DJ JIN |
| 20 | Hopes And Dreams (Remixed by tofubeats) | 3:39 | tofubeats |
UNDERTALE Piano Arrangement Album - Echoes Beneath is the second album produced for the collaboration, released on February 25, 2026. It was produced by Yoko Shimomura.
| No. | Title | Length | Author |
|---|---|---|---|
| 1 | Once Upon a Time (Arranged by Ryota Kikuchi) | 1:58 | Ryota Kikuchi |
| 2 | Ghost Fight (Arranged by Yuki Kishida) | 2:46 | Yuki Kishida |
| 3 | Heartache (Arranged by Yui Morishita) | 3:51 | Yui Morishita |
| 4 | Nyeh Heh Heh! (Arranged by Ryota Kikuchi) | 2:19 | Ryota Kikuchi |
| 5 | Waterfall (Arranged by Yuki Kishida) | 2:29 | Yuki Kishida |
| 6 | Spear of Justice (Arranged by Yui Morishita) | 4:25 | Yui Morishita |
| 7 | Can You Really Call This A Hotel, I Didn't Receive A Mint On My Pillow Or Anything (Arranged by Yuki Kishida) | 2:49 | Yuki Kishida |
| 8 | Death By Glamour (Arranged by Ryota Kikuchi) | 5:49 | Ryota Kikuchi |
| 9 | Undertale (Arranged by Yuki Kishida) | 5:30 | Yuki Kishida |
| 10 | Don't Give Up (Arranged by Yui Morishita) | 2:17 | Yui Morishita |
| 11 | Hopes And Dreams (Arranged by Ryota Kikuchi) | 5:27 | Ryota Kikuchi |
| 12 | His Theme (Arranged by Yuki Kishida) | 2:08 | Yuki Kishida |
| 13 | Respite (Arranged by Yui Morishita) | 3:37 | Yui Morishita |
| 14 | MEGALOVANIA (Arranged by Yoko Shimomura/Yui Morishita) | 3:56 | Yoko Shimomura, Yui Morishita |
| 15 | Good Night (Arranged by Ryota Kikuchi) | 1:08 | Ryota Kikuchi |
Japanese-exclusive magazines that were dedicated to the 10th Anniversary.
Issue #1914 of the Famitsu magazine was dedicated to Undertale with some Deltarune content, and was released on September 11, 2025. It features three interviews:
- 8-4's Hiroko Minamoto and John Ricciardi, where they detail their experiences with working with Toby Fox and Keiko Fukuichi and localizing Undertale and Deltarune.
- Toby answers ten questions.
- An interview with Fangamer JP staff.
The magazine also offers a recap of Undertale's story and themes and Deltarune's Chapters up to Chapter 4, brief summaries some of Undertale and Deltarune characters, excluding the protagonist, the fallen human, and Asriel, and a timeline of Undertale and Deltarune's history.
- Undertale's Anniversary section
- Deltarune's Anniversary section on the Deltarune Wiki
- Spamton Sweepstakes article on the Deltarune Wiki
- ↑
Audrey made the final #UT10th logo, and the JP concert logo.
— @everdraed.bsky.social on Bluesky, September 23, 2025.
I wanted to see the concert piano at a different angle so I MSPainted it, but that exposed the hands. the ultra realistic piano-playing hands.
I am sorry.
but they have no pain... - ↑
Huge thanks to Toby, @84play and @FangamerJP giving us such an opportunity. Hope you enjoyed it and see you soon with our live performance!
— @musicengine_tw on Twitter, September 16, 2020. - ↑
❤️祝『UNDERTALE』10周年！
— @musicengine_tw on Twitter, September 15, 2025.
そしてこの記念の日に「UNDERTALE 10th Anniversary Concert」大阪での全5公演が無事終了しました！
初めて『UNDERTALE』の公演を行った8年前には、まさかこんな機会をいただけるとは思ってもいませんでした。
Toby Foxさん、8-4さん、Fangamerさん、また今回の公演にお越しいただいた方々はもちろん、これまで応援して下さった全ての方に御礼申し上げます。
来月は東京・横浜にて公演を行います。
引き続きみなさまと一緒に『UNDERTALE』の10周年をお祝いできるのを楽しみにしています！ - ↑
大きな違いのひとつとして、Cプログラムでは「本物のヒーローとの戦い」「"NEO"の力」「MEGALOVANIA」は演奏いたしません。
— 【公式】UNDERTALE 10th Anniversary Concert (Kawai, Kota, March 04, 2026.) undertale10thconcert.com.
「誰も傷つかなくていい」というUNDERTALEが持つ本質的な魅力を大切にし、その世界観をイメージして選曲を行いました。 - ↑
Greetings Humans,
— @undertalesymph on Twitter, March 17, 2026.
UNDERTALE: The Determination Symphony is coming to a city near you!
🎻Follow the journey through the Underground as the iconic soundtrack is performed live by an orchestra with synchronized gameplay footage on screen.
🎟️Presale tickets for most dates start March 18th @ 10am local time.
Sign up for the Tour Newsletter to receive the presale code: undertalesymphony.com/#newsletter - ↑
UNDERTALE 10TH ANNIVERSARY ORCHESTRAL CONCERT 👾
— @ljprods on Twitter, March 28, 2025.
We are ecstatic to announce the Determination Symphony - a one-night-only orchestral concert featuring Toby Fox’s legendary music from the game Undertale. 🎶 - ↑
You’re gonna have a good time. 💀 The Undertale 10-Year Anniversary Remixes are out now! 🎧 monster.cat/undertale-remixes
— @monstercat on Twitter, October 06, 2025.
✨ 10 iconic tracks from the Underground, remixed by Monstercat and Firaga artists from the Surface.
Which remix fills you with DETERMINATION? 👇 - ↑
Monstercat has officially fallen into the Underground! 🕹️✨
— @monstercat on Twitter, September 12, 2025.
We’ve teamed up with Undertale, Materia, and Firaga Records to celebrate a decade of determination with the Undertale 10th Anniversary Remix Album: 10 iconic songs, completely reimagined.
🎵 A fresh remix drops every Monday starting September 22 until the full album arrives on October 6. 😻 Pre-save it here: monster.cat/undertale-remixes
👀 Who do you think is taking on these legendary tracks? - ↑
Human, watch out! 👀 @TokyoMachine is on watch and ready to hook you with his remix of “sans.” from Undertale - OUT NOW! 💀 monster.cat/tm-sans
— @monstercat on Twitter, September 22, 2025.
And that’s not all... This Thursday, we’re revealing the full tracklist for the official Undertale 10-Year Anniversary Remix Album! 😼 - ↑
Real drama!!
— @monstercat on Twitter, September 29, 2025.
Real action!!
Real bloodshed!!
‼️
@vgremixes is ready to take on METTATON EX with his powerful Undertale "Death By Glamour" Remix - OUT NOW! 🤖 monster.cat/vgr-deathbyglamour
