Welcome to the Underground

Everything about Undertale

A fan guide for Toby Fox's RPG where mercy, choices, hidden details and unforgettable music matter as much as battles.

Undertale logo
CreatorToby Fox
Release15 Sep 2015
GenreIndie RPG
Core ideaNo one has to die

About Undertale

Undertale is a 2D role-playing video game created by independent developer Toby Fox. The player controls a child who has fallen into the Underworld: a large region below the Earth's surface, isolated by a magical barrier. The player encounters various monsters on their journey to the surface. Some of the monsters will engage the player in combat; the player must fight their way through the bullet hell attacks of their opponents. The player can choose not to kill the monsters, but to appease or subdue them, in order to spare them. These choices affect the course of the game: dialogue, characters, and story can change considerably.

Undertale is a role-playing game; the player looks down on the world from above and controls a child, completing objectives so that the story can progress. The player explores an underground world, full of towns and caves, and must solve numerous puzzles to move forward. Various monsters live in the underground world; many of them challenge the player to battle; the player decides whether to kill their opponent, flee, or befriend them. The player's choices radically affect the direction of the story, their morality being the foundation on which the action is built.

The game was released for Microsoft Windows and Mac OS X in September 2015. It was also ported to Linux (in July 2016), PlayStation 4, PlayStation Vita (both in August 2017), Nintendo Switch (in September 2018), Xbox One, and Xbox Series X/S (both in March 2021). The game received positive reviews for its thematic material, intuitive battle system, originality, story, dialogue, and characters. The game has sold over one million copies and received numerous awards and nominations. Several publications and conventions have named Undertale as their "game of the year". The first chapter of a closely related game, Deltarune, was released in October 2018.

Battle system

Gameplay that remembers your choices

Undertale mixes top-down exploration, puzzles and bullet-hell battles. The unusual part is that combat can be solved through observation, dialogue, jokes, patience and mercy.

ACT selected

Read the opponent

Click a mechanic card to change the battle box animation and learn what the mechanic does.

ACT

Read the opponent

Every monster has personality. The ACT menu turns battles into tiny social puzzles.

SPARE

Mercy is a mechanic

You can win many encounters without killing, which changes dialogue and route outcomes.

SOUL

Dodge inside the box

Enemy turns become moving patterns where the heart changes modes, colors and rules.

SAVE

The game notices

Saves, resets and previous actions are part of the story, not just background systems.

Choices matter

Main routes and endings

The story changes depending on what you do in encounters. The most important paths are Neutral, True Pacifist and Genocide, with Hard Mode acting as a short special challenge.

Choose a route card to open an animated route briefing.

Neutral Route

Reached when the run does not meet the strict Pacifist or Genocide conditions.

  • Many ending phone calls
  • Choices still matter
  • Good route for a first blind playthrough

True Pacifist Route

The hopeful path: spare everyone, build friendships and uncover the full emotional ending.

  • No monster kills
  • Friendship events matter
  • Leads to freedom for the Underground

Genocide Route

The darkest path, built around clearing areas and forcing the game into confrontation.

  • Major character changes
  • Hardest boss encounters
  • Heavy consequences for the player

Hard Mode

A short alternate mode triggered by naming the fallen human Frisk.

  • Ends after the Ruins
  • Changes early encounters
  • More of a joke/challenge than a full route

Where to play

Platforms and official places

Undertale is available on PC, Nintendo Switch, PlayStation and Xbox. Physical editions and collector items are connected to Fangamer, while the digital PC version is also on Steam and GOG.

PC / Mac / Linux Original release, fast access to mods, guides and soundtrack listening.

PC / Mac / Linux

Original computer release, with Steam and non-Steam download options.

Steam page

Nintendo Switch

Portable and TV play, plus physical and collector editions listed on the official site.

Official site

PlayStation

PS4 and PS Vita versions include playful trophy support and Cross-Buy for digital copies.

FAQ

Xbox

Playable on Xbox One and Xbox Series X/S, with achievements adapted for the platform.

Availability

Undertale

by Toby Fox

Undertale Timeline

The Story of Undertale

Click on the panel or press Next to continue the story.

PART I

A Long Time Ago...

1 / 8

You can also use Enter, Space, Left Arrow and Right Arrow.

Spoiler zone

Secrets and mysteries

Undertale hides meaning in small details: names, dialogue changes, save files, rare rooms and strange characters. This section gathers the biggest mystery areas without breaking the rest of the site.

W.D. Gaster

The missing scientist

Gaster is one of Undertale's best-known mysteries: a royal scientist connected to fragments, rare encounters and hints that feel deliberately incomplete.

FUN values

Some rare events depend on hidden values, which is why players can miss them for years.

These hidden values can change rooms, NPC appearances and strange dialogue.

Name secrets

Specific names at the start trigger jokes, warnings or special modes.

Some names are refused, some tease the player, and Frisk starts Hard Mode.

True Lab

A late-game area that changes how you understand Alphys, determination and the story.

Its logs connect determination experiments with the Amalgamates.

Reset memory

Some characters and systems react as if the world has already happened before.

Flowey and Sans are the clearest signs that resets are part of the fiction.

Undertale

by Toby Fox

Creepypasta

Soundtracks

Console achievements

Trophies and achievements

Build your own achievement route. Pick a category, inspect the task, mark what you completed and feed the Dog Shrine to unlock a stranger ending to the board.

Achievement route

Choose a task from the board

Select an achievement card to see how it fits Undertale's console trophy joke.

0% complete. The board is still watching.

Story

Reach a new area

Track milestones like Ruins, Snowdin, Waterfall, Hotland and CORE.

Ending

Finish a route

Neutral, Pacifist and Genocide routes change what achievement hunting means.

Items

Fill the inventory

Some trophies reward simple item collection, poking fun at how easy achievements can be.

Dog Shrine

Donate enough gold

Donation levels turn a tiny side joke into a whole achievement ladder.

Undertale Shop

Choose your favorite products

Human souls shirt

Human souls shirt

Black 100% cotton T-shirt

15€

Space junk shirt

Space junk shirt

Black 100% cotton T-shirt

15€

Sans plushie

Sans plushie

Sans character plushie

20€

Toriel plushie

Toriel plushie

Toriel character plushie

20€

Chara plushie

Chara plushie

Chara character plushie

20€

Papyrus plushie

Papyrus plushie

Papyrus character plushie

20€

Fan hub

Community and official links

Undertale stayed alive because fans kept discussing routes, music, theories, art and speedruns. The official site also links to news, the mailing list, merch and Deltarune updates.

Newsletter and updates

Follow official UNDERTALE / DELTARUNE updates from Toby Fox and the official site.

Newsletter and updates

Follow official UNDERTALE / DELTARUNE updates from Toby Fox and the official site.

Official website

Official merch

Collector editions, apparel, music items and physical releases are connected through Fangamer.

Fangamer

Music culture

The soundtrack is one of the biggest reasons fans return to Undertale years later.

Open soundtrack

Theory corner

Gaster, resets, souls and Deltarune connections keep the lore community busy.

Read secrets

Underground Timeline

Upcoming Undertale Events

Discover the next fan activities, challenges and special moments from the Underground.

Undertale Quiz

Show your knowledge about Undertale!

Underground Journal

Undertale Blog

Read short articles about the world, characters and hidden meanings of Undertale.

Main contact

Contact us

Questions? Complete the spaces below:

Useful information

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eduarddanciu2012@gmail.com

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