Undertale is Toby Fox's 2015 role playing game about a child who falls into the Underground and has to find a way out. Its hook is that every encounter can be ended without killing: you dodge patterned attacks inside a small box, then use ACT and MERCY instead of FIGHT. A single run takes roughly six to seven hours, and the game quietly records what you chose to do along the way.
Starting Undertale can feel overwhelming. This guide tells you exactly what to focus on during your first hours so you don't waste time on things that don't matter yet. For the full progression path, see our walkthrough.
What Kind of Game Is This?
Undertale is a rpg game built around Bullet dodging in the SOUL box and FIGHT, ACT, ITEM and MERCY. The core loop involves mastering these systems to progress through increasingly challenging content.
What to expect: Time investment in learning mechanics, experimentation, and gradual mastery. The game rewards patience and knowledge.
Choosing Your First Build
| Build | Beginner Rating | Why |
|---|---|---|
| Neutral Route | Excellent for beginners | Balanced approach |
| True Pacifist Route | Excellent for beginners | Balanced approach |
| Genocide Route | Excellent for beginners | Balanced approach |
| Hard Mode | Excellent for beginners | Balanced approach |
| No Hit Challenge Run | Excellent for beginners | Balanced approach |
Our recommendation: Start with True Pacifist Route. It offers the most forgiving experience while teaching core mechanics.
Avoid No Hit Challenge Run as your first pick. It requires deep knowledge of game systems to use effectively. Once you're ready, check our classes guide for all options.
First Session Step-by-Step
Step 1: Learn Bullet dodging in the SOUL box
On an enemy turn your SOUL becomes a small red heart inside a rectangular box and you dodge projectile patterns with the arrow keys. You start on 20 HP, so two or three clean hits from a mid game attack is fatal.
This is the foundation. Spend your first 15-30 minutes getting comfortable with how Bullet dodging in the SOUL box works before worrying about anything else. Our combat guide breaks this down further.
Step 2: Head to The Ruins
The opening area, a purple stone maze of switch and rock puzzles under Toriel's care. It teaches ACT through Froggits and Whimsuns, hides the Toy Knife and Faded Ribbon, and closes with the game's first real boss fight.
Clear the main content here before moving on. Everything teaches fundamentals you'll need later. See our maps guide for all locations.
Step 3: Get Your First Upgrade
Look for Toy Knife: it's the most accessible early upgrade. 3 attack, found in the Ruins. The first real upgrade and the earliest signal that the game will arm you if you decide you want that.
Step 4: Understand FIGHT, ACT, ITEM and MERCY
FIGHT uses a timed bar where stopping the cursor dead centre deals maximum damage. ACT holds enemy specific options like Check, Flirt or Compliment, and using the right ones turns the enemy's name yellow in the MERCY menu so it can be spared.
This is the system most new players overlook. Invest time here early. It pays off throughout the entire game.
Step 5: Push to Snowdin
A snowfield and town run by Papyrus and Sans, with a run of deliberately silly puzzles, a set of dog themed enemies and a shop stocking the Tough Glove and Manly Bandanna. It is the most forgiving stretch of the game.
Essential Mechanics Explained
Bullet dodging in the SOUL box
On an enemy turn your SOUL becomes a small red heart inside a rectangular box and you dodge projectile patterns with the arrow keys. You start on 20 HP, so two or three clean hits from a mid game attack is fatal.
FIGHT, ACT, ITEM and MERCY
FIGHT uses a timed bar where stopping the cursor dead centre deals maximum damage. ACT holds enemy specific options like Check, Flirt or Compliment, and using the right ones turns the enemy's name yellow in the MERCY menu so it can be spared.
LOVE, EXP and LV
EXP stands for Execution Points and LV stands for LOVE, and both rise only when you kill. Staying at LV1 keeps you on 20 HP for the entire game, while LV20 puts you on 99 HP, so it is a difficulty setting as much as a moral one.
Coloured SOUL modes
Several bosses recolour your SOUL and change the rules entirely. Blue drops you to the bottom of the box so you jump, green pins you in place behind a directional shield, yellow lets you shoot back, and purple traps you on horizontal lines.
Route tracking across a whole run
The game counts kills, spares, deaths and dialogue choices, and it holds those counts across saves. Which of the three main endings you reach depends on what those counters say when you get to the end.
Common Beginner Mistakes
1. Killing a handful of monsters early and then aiming for True Pacifist
Any kill at all blocks it for that run.
2. Spamming FIGHT on Toriel because the ACT options look like they are doing nothing
Sparing her takes many attempts and the game expects persistence.
3. Walking past every shop and reaching the endgame with three items and no armour
4. Selling the Butterscotch Pie for gold
It heals 64 HP and has a specific extra effect in one late fight.
5. Sampling the Genocide route out of curiosity and assuming a reload undoes it
The game keeps records across saves.
First 5 Hours Checklist
- Understand Bullet dodging in the SOUL box and FIGHT, ACT, ITEM and MERCY
- Choose True Pacifist Route as starting build
- Clear The Ruins main content
- Acquire Toy Knife or equivalent upgrade
- Reach Snowdin
- Use Check on every new enemy before anything else. The flavour text points at the ACT option that will spare it, and it costs one turn you were going to spend dodging anyway.
- Toriel's phone number is not decoration. Calling her from different rooms produces different lines, and in the Ruins the phone is part of how the area is meant to be played rather than an optional extra.
Tips for New Players
- Use Check on every new enemy before anything else. The flavour text points at the ACT option that will spare it, and it costs one turn you were going to spend dodging anyway.
- Toriel's phone number is not decoration. Calling her from different rooms produces different lines, and in the Ruins the phone is part of how the area is meant to be played rather than an optional extra.
- Buy at least one Spider Donut or Spider Cider from the bake sale in the Ruins. Muffet in Hotland checks whether you supported the spiders and behaves very differently if you did.
- Temmie Armor lists at 9999G, more gold than a normal run produces. Talk to the Temmie asking for college money and pay repeatedly until the price falls to 1000G, at which point 20 defence carries you through almost anything.
- Sparing is often a sequence, not a single action. Some enemies need several ACT commands in order and some need their partner spared first, which is why the dog family in Snowdin catches new players out.
- Green SOUL mode in the Undyne fight removes your ability to move at all. You hold a directional shield instead, so read the direction each spear comes from and face it rather than trying to dodge sideways.
- Yellow SOUL mode inverts the game during Mettaton encounters and lets you shoot upward. Keep firing between dodges, because both damage and the on screen ratings depend on how much you put out.
- Every save point is also a full heal, and one sits before each major fight. If you walk into a boss on damaged HP, you walked past a save point.
- The True Pacifist ending requires zero kills across the entire run, not just the closing chapters. One accidental kill in the Ruins blocks it until you finish a neutral ending and go back through.
- The Genocide route is a grind rather than a rush. Each area has to be emptied until random encounters stop spawning, and two of its fights are far harder than anything on the other routes.
Frequently Asked Questions
How long is Undertale?
A single route runs roughly six to seven hours. Seeing all three main endings, including True Pacifist and Genocide, takes closer to 20 hours in total.
Do I have to kill anything?
No. Every enemy in the game, bosses included, can be resolved through ACT and MERCY. Finishing with zero kills is the requirement for the True Pacifist ending.
What do EXP and LV actually mean?
EXP is Execution Points and LV is LOVE. Both rise only from killing, and both raise HP, attack and defence. LV1 leaves you on 20 HP for the whole game while LV20 puts you on 99.
Which route should I play first?
Neutral, without reading anything first. The game is built around reacting to uninformed choices, and the pacifist ending is designed to be reached after a neutral ending rather than before it.
Is Deltarune a sequel?
No. Deltarune is a separate Toby Fox project that shares characters and art style without continuing Undertale's story. Undertale itself released on 15 September 2015.
More Undertale Guides
- Undertale Undertale Overview
- Undertale Best Builds
- Undertale Tier List
- Undertale Walkthrough
- Undertale Tips & Tricks
- Undertale Weapons Guide
- Undertale Combat Guide
- Undertale Boss Guide
- Undertale Maps & Locations
- Undertale Crafting Guide
- Undertale Classes & Characters
Similar Games
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- Baldur's Gate 3 Beginner's Guide: rpg game with similar mechanics
- Cyberpunk 2077 Beginner's Guide: rpg game with similar mechanics
