Undertale facts for kids

Quick facts for kids Undertale
Developer(s)	Toby Fox
Publisher(s)	Toby Fox 8-4
Designer(s)	Toby Fox
Artist(s)	Temmie Chang Toby Fox
Composer(s)	Toby Fox
Engine	GameMaker Studio
Platform(s)	OS X Windows Linux PlayStation 4 PlayStation Vita Nintendo Switch Xbox One
Release date(s)	September 15, 2015 OS X, Windows September 15, 2015 Linux July 17, 2016 PS4, PS Vita August 15, 2017 Nintendo Switch September 18, 2018 Xbox One March 16, 2021
Genre(s)	Role-playing
Mode(s)	Single-player

Undertale is a popular adventure game where you play a special role, created in 2015 by an independent developer named Toby Fox from America. In this game, you control a child who accidentally falls into a hidden world deep underground. This world, called the Underground, is sealed off from the surface by a powerful magic barrier.

As you explore, you meet many unique monsters. Some of them might challenge you to battles. The combat system is exciting, asking you to dodge many fast attacks, almost like a mini-game. But here's the cool part: you don't have to fight! You can choose to talk to the monsters, understand them, and even become friends. Your choices in these encounters change the story, the characters you meet, and how the game unfolds.

Toby Fox made almost the entire game himself, including the story and music. Only the artwork and character designs had help from Temmie Chang and a few other artists. Undertale got ideas from many other games like Mario & Luigi and Mother, as well as dodging games like Touhou Project. It even took inspiration from the British comedy show Mr. Bean!

The game first came out for computers (OS X and Windows) in September 2015. Later, it became available on Linux in 2016, PlayStation 4 and PlayStation Vita in 2017, Nintendo Switch in 2018, and Xbox One in 2021. People loved Undertale for its unique story, fun battles, amazing music, and memorable characters. It has sold over five million copies and is seen as one of the greatest video games ever made. A related game with a different story, called Deltarune, started releasing chapters in 2018. Its first four chapters were released as a full package in June 2025.

Exploring the Underground: How to Play

In Undertale, you control a red heart to dodge enemy attacks. You can choose to fight, talk, or spare monsters during battles.

Undertale is an adventure game played from a top-down perspective, meaning you look down on your character from above. You guide a child through a magical underground world filled with towns, caves, and many puzzles to solve. This world is home to all sorts of monsters. Many monsters will challenge you to a fight, but you get to decide what happens next. You can choose to fight them, run away, or even try to make friends! Your choices are very important and will change the story and how the game unfolds.

Battle System: Fight, Act, or Spare

When you meet an enemy, you enter a special battle mode. In battle, you control a small red heart, which represents your soul. You must move this heart to avoid attacks from the monster, much like a dodging game. As you play, new challenges appear, like colored obstacles and unique boss battles that change how you control your heart.

You have several options during a fight:

• Attack: You can choose to attack the enemy by pressing a button at the right time. If you defeat enemies this way, you earn EXP (Experience Points) and gold.
• ACT: This option lets you learn more about the monster. You can check their strengths and weaknesses, or perform special actions that are different for each monster.
• Item: You can use items to heal yourself or help in other ways.
• Mercy: If you use the right "ACT" actions, or if you weaken an enemy enough without defeating them, you can choose to "Spare" them. This ends the fight peacefully without anyone getting hurt.

To finish some boss battles peacefully, you just need to survive their attacks until they finish talking. The game has many different story paths and endings based on whether you choose to fight or spare your enemies. It's even possible to finish the entire game without defeating a single monster!

Smart Monsters and Changing Stories

Monsters in Undertale are very clever. They will talk to you during battles, and the game will even tell you what they are feeling. Their attacks can change based on how you interact with them, and even become harder or easier. The game also remembers your past actions. If you play through the game a second time and reach a boss you fought before, their dialogue might be different because the game remembers what you did!

The Story of the Underground

The story of Undertale takes place in a hidden world called the Underground. Long ago, a war happened between humans and monsters, and the monsters were sent to live underground. A powerful magic barrier, with only one way in or out at Mount Ebott, sealed them away.

Your Journey Begins

At the start of the game, you, a human child, fall into the Underground from Mount Ebott. You quickly meet Flowey, a talking flower who tries to trick you. Luckily, Toriel, a kind, goat-like monster, saves you. She teaches you how to survive without fighting and wants to adopt you to keep you safe from Asgore, the king of the Underground.

You eventually decide to leave Toriel to find Asgore's castle, which holds the key to breaking the barrier and returning to the surface. Along the way, you meet many memorable characters:

• The funny skeleton brothers, Sans and Papyrus, who guard the snowy forest.
• Undyne, the brave leader of the royal guard.
• Alphys, the kingdom's shy royal scientist.
• Mettaton, a flashy robot TV star created by Alphys.

You will face most of these monsters in battle, and your choice to fight or befriend them will shape your adventure.

The History of the Barrier

During your travels, you learn about the past. Many years ago, Asriel, the son of King Asgore and Queen Toriel, became friends with the first human child who fell into the Underground. When that child passed away, Asriel used their soul to cross the barrier, hoping to return the child's body to the surface. However, the humans on the surface misunderstood and attacked Asriel, causing him to pass away too. This sad event made King Asgore declare war on humans. In the present day, Asgore has collected six human souls and needs one more to finally break the magic barrier.

Creating Undertale: The Development Story

Undertale was created by Toby Fox over 32 months. He funded the game through a crowdfunding campaign on Kickstarter. The campaign started in June 2013, aiming for $5,000, but ended up raising over $51,000 from nearly 2,400 people! Toby Fox didn't have much experience making full games before this. He used to make small role-playing games with his brothers using a tool called RPG Maker 2000. He was also known for composing music for the webcomic Homestuck. Undertale was his first complete game.

The name Undertale was inspired by other games Toby liked, like EarthBound and Cave Story, which had two words in their titles. He wanted a name that was catchy and fit the game's underground setting.

Game Design Choices

Toby Fox wanted to make a role-playing game that felt fresh and different from traditional ones, which he sometimes found "boring." He aimed to create a game with "interesting characters" and a story that truly used the game world to tell its tale. He worked on the entire game mostly by himself to keep his vision clear. Temmie Chang was the main artist, creating most of the character sprites and concept art. Toby believed that simple art styles could make characters more relatable and fun.

The dodging part of the battle system was inspired by games like the Mario & Luigi series and fast-paced dodging games like Touhou Project. Toby wanted the battles to be fun and engaging, like in Super Mario RPG. He also made sure that players wouldn't need to "grind" (repeatedly fight enemies to get stronger) or do "fetch quests" (simple tasks that involve a lot of going back and forth), as he didn't enjoy those in other games. He made the game's difficulty just right, so even players new to dodging games could enjoy it.

The idea of talking to monsters instead of fighting them came from games like Shin Megami Tensei. Toby wanted to expand on this idea, making it possible to finish the game without hurting anyone. He was also inspired by Moon: Remix RPG Adventure, a game where you help people instead of fighting.

Writing the Story and Characters

Toby Fox found inspiration for the game's world and story from the idea of being trapped underground, like in the game Brandish. He also drew ideas from funny internet culture and comedy shows like Mr. Bean. He wanted to challenge common ideas found in many games. He felt that writing became easier once he understood each character's voice and personality. He also wanted each monster to feel unique, unlike how some games make all monsters seem the same.

Toriel, one of the first characters you meet, was designed to be a helpful "mom" figure. Toby wanted her to genuinely care about the player, unlike some tutorial characters in other games that give too many hints. Initially, players had to defeat Toriel to continue, but Toby changed this before the game's demo was released. This decision helped him realize the core message of Undertale: the choice to spare monsters.

Sans and Papyrus are named after the fonts Papyrus and Comic Sans, and their dialogue appears in these fonts in the game. Papyrus was first a meaner character, but Toby changed him. Sans was originally planned to tell more jokes. Toby said one of the most memorable parts of making the game was when Papyrus rejects Frisk during their date, which was made less harsh after a playtester cried during the scene.

The Music of Undertale

Toby Fox composed the entire soundtrack for Undertale himself using a program called FL Studio. He taught himself music and created most songs quickly. The game's main theme, "Undertale," was one of the few songs that took many tries to get just right. The music was inspired by classic Super NES role-playing games like EarthBound, dodging games like Touhou Project, and the webcomic Homestuck. Toby composed the music for each section of the game before programming it, as it helped him decide how the scene should feel.

The soundtrack has been highly praised by critics. Many loved how Toby used "leitmotifs" (recurring musical themes) for different characters throughout the game. For example, the song "Hopes and Dreams," played during a big boss battle, uses parts of many main character themes, making it a perfect way to end your journey. This shows Toby's skill at turning old songs into new experiences. The music has been covered by many artists and groups, and there have even been live concerts of Undertale songs in Japan.

Release and Beyond

Undertale was first released as a demo in May 2013. The full game launched on September 15, 2015, for OS X and Windows computers. It later came to Linux in July 2016.

Console Releases

The game also made its way to consoles:

• PlayStation 4 and PlayStation Vita in August 2017. These versions included special unlockable achievements and a new area called the Dog Shrine.
• Nintendo Switch in September 2018. This version featured an exclusive boss fight against Mad Mew Mew.
• Xbox One in March 2021. This version added a playable slot machine in the Dog Shrine.

All console versions were developed and published by a Japanese company called 8-4.

Merchandise and Music

Many Undertale items have been released, including toy figures and plush toys of the characters. The official soundtrack was released on the same day as the game. There are also official cover albums, like a metal/electronic album called Determination and jazz albums like Live at Grillby's. Piano sheet music books and digital albums have also been released.

In September 2019, a Mii Fighter costume based on Sans became available for Super Smash Bros. Ultimate, along with a new version of the song "Megalovania". The director of Super Smash Bros. noted that Sans was a very popular request from fans.

Japanese Translation

After Undertale became popular in Japan, Toby Fox decided to create an official Japanese translation. He chose the company 8-4, known for translating other games. To make sure the translation felt just right, only one main translator, Keiko Fuchicho, worked on it. Toby Fox provided notes and advice throughout the process. The Japanese version was released for PS4 and Vita in August 2017, and for PC in August 2017. Fans were surprised by some choices, like using a specific Japanese pronoun for Sans, which became known as "oira shock."

Impact and Legacy

Undertale quickly gained a huge and dedicated fan base. About a year after its release, Toby Fox was surprised by how popular the game had become. He felt grateful but also a bit overwhelmed by all the attention. Many people, including Ana Diaz from NPR, have said that Undertale influenced the entertainment tastes of a whole generation, especially through internet memes. The character Sans is especially popular and has inspired many fan creations. Even professional wrestler Kenny Omega dressed as Sans for a TV show!

Fan Community and Challenges

The Undertale fan community has also faced some challenges. Sometimes, fans disagreed strongly about the "right" way to play the game. Some online streamers felt pressured by other fans about how they played, especially if they chose to fight monsters. For example, YouTuber Markiplier decided not to finish his first playthrough because of strong fan opinions. Despite these challenges, the fandom has created many amazing fan games, like the highly anticipated Undertale Yellow, which was released in 2023 and became very popular.

Awards and Recognition

Undertale received many awards and nominations for its story, characters, and unique gameplay. It was named Game of the Year by several gaming publications and conventions in 2015.

Some of its notable awards and nominations include:

• IGN's Best of 2015: Won Best Story.
• Independent Games Festival: Won the Audience Award.
• SXSW Gaming Awards: Won Most Fulfilling Crowdfunded Game and the Matthew Crump Cultural Innovation Award.
• Japan Game Awards: Received an Award for Excellence in 2018.

In 2019, Polygon listed Undertale among the best games of the decade. In 2021, IGN ranked it as the 20th greatest game of all time, and in Japan, a large TV poll placed it as the 13th greatest game ever.

Spin-off: Deltarune

After hinting at a new project, Toby Fox released the first chapter of Deltarune for free on October 31, 2018, for computers. Toby Fox has explained that Deltarune is not the same world as Undertale, but you might recognize some characters and places. It's meant for players who have already finished Undertale. The name Deltarune is actually an anagram (a rearrangement of letters) of Undertale.

Toby Fox mentioned that Deltarune is a bigger project than Undertale. It took him several years to create just the first chapter, much longer than the Undertale demo. Unlike Undertale, Deltarune is designed to have only one main ending, no matter what choices you make.

Chapter 2 of Deltarune was released for free on September 17, 2021. Toby Fox gathered a team to help him with the rest of the game. Chapters 1 through 4 were released as a paid package on June 4, 2025. All future chapters will be released as free updates once they are ready.

Images for kids

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  Cosplayers portraying (from left to right) Sans, Undyne, Papyrus, Toriel, Grillby, and Napstablook at Tsunacon in Rotterdam

See also

In Spanish: Undertale para niños