UNDERTALE: How to Defeat or Spare Undyne

Basic Information about Undyne

Boss in Waterfall for the N and P Routes

Undyne is the boss fought at the end of the Waterfall area in both the Neutral and Pacifist routes. In the Genocide Route, she appears in a different form as "Undyne the Undying," which is different from the N and P routes.

Tips for Beating Undyne

Prepare Healing Items

Before the battle with Undyne, make sure to obtain healing items such as "Astronaut Food" or "Dog Salad". If you have enough gold, it is recommended to buy "Sea Tea" from the shop or go back to Snowdin and purchase "Bisicle".

Block Attacks When the Soul is Green

When the soul is green, use the Arrow Keys or Left Stick to block the incoming attacks. If you fail to block the attacks, they will hit the soul and cause damage.

Yellow Arrows Indicate Attacks from the Opposite Direction

Attacks with yellow arrows are different from regular attacks. They will come from the opposite direction and hit you. Don't be fooled by the direction they come from. Use the opposite direction on the Arrow Keys to defend against the attacks.

Dodge or Flee from Attacks When the Soul is Red

When the soul is red, you have the option to choose "Flee" from the "Mercy" command. If you choose to heal with an item, you will still get hit by the attacks. Move the soul to avoid the spears coming from random directions.

How to Spare Undyne

Defending Against Undyne's Attacks

When the battle with Undyne begins, the soul will turn green and you won't be able to escape. Choose "Challenge" to "Confront" or "Dodge" to "Evade" while defending against her attacks. Keep defending until the soul turns red to buy more time.

Select Run Away When the Soul Turns Red

When the soul turns red, you can select "Run Away" and head towards Hotland. Even if you escape, Undyne will catch up and attack again, so you need to repeat this process until she stops attacking.

Undyne Collapses from the Heat and the Battle Ends

Upon arriving in Hotland, Undyne's attacks stop and she collapses from the heat. If you proceed while Undyne is still down, the battle will automatically end.

Giving Water is Necessary for the Friendship Event to Occur

When Undyne collapses from the heat, giving her the water from the water cooler will also end the battle. Since giving water is a requirement for triggering the Friendship event with Undyne, if you want to proceed with the P route, don't leave immediately and head towards the water cooler.

Undyne's Attack Patterns and How to Defend

Undyne is a formidable opponent in battle, but with the right strategies, you can overcome her attacks. Here, we will discuss Undyne's attack patterns and how to effectively defend against them.

Spear Thrust

Undyne often starts the battle by thrusting her spear towards you. To defend against this attack, you need to time your movements carefully. As soon as you see her preparing to thrust, quickly move in the opposite direction to avoid getting hit.

Green Arrows

Undyne may also shoot green arrows towards you. These arrows move rapidly, making them difficult to dodge. However, there is a trick to avoiding them. Stay still and observe the arrows closely. Once you understand their pattern, move through the gaps between them to avoid getting hit.

Shield Bash

Undyne occasionally uses her shield to bash you. This attack can be quite powerful, so it's important to be prepared. When you see her raising her shield, quickly move away to create distance. This will minimize the impact of her bash and give you time to recover.

Water Blasts

Undyne has the ability to shoot powerful water blasts at you. These blasts can cover a wide area, making them challenging to avoid. To defend against them, keep moving and stay alert. Try to predict where the blasts will land and move away from those areas to stay safe.

Remember, practice is key when facing Undyne. By mastering her attack patterns and staying focused, you can increase your chances of defeating her. Good luck!

Green Attack

	Attack	Attack Pattern	Defense
①		↑×3	Up 3 times
②		↑, ↑←, ←→, →	Up 2 times, Left 2 times, Right 2 times
③		←, →, ←→, →←, ←, ↓	Left, Right, Left, Right 2 times, Left 2 times, Down
④		↑, →, ↓, ←↑, →, ↓, ←↑×4	Counter-clockwise: Up, Right, Down, Left twice, Up 4 times
⑤		←, ↑, ↑→, ↑, ↑←, ↑, ↓	Left, Up 2 times, Right, Up 2 times, Left, Up, Down
⑥		←, ↑, ↓, →←, ↑, ↓, →↓, ↑Spear attack from the left	Left, Up, Down, Right twice, Down, UpMove down immediately when it turns red
⑦		↑, ↓, ↑, ↓↓, ↑, ↓, ↑	Up, Down, Up, Down 2 times, Up, Down, Up
⑧		↑, →, ↓↑, →, ↓, →	Up, Right, Down twice, Up, Right, Down, Right
9		←×3→×3↓, ↑, ↓, ↑	Left 3 times, right 3 times, down, up, down, up
10		→×5←, ←, →↓, ←, ↑, ↑Spear attack from the left	Left 5 times, Right 2 times, Left, Down, Left, Up 2 timesMove down immediately when it turns red
11		→, ←→, ←, ←	Right, Left, Right, Left 2 times
12		←, →, ↑, ↓←, →, ↑, ↑	Left, right, up, downLeft, Right, Up, Up
13		←, ↓, →, ↑←, ↓, →, ↑	Counterclockwise, Left, Down, Right, Up
14		←, ←, →, →↓, ↓, ↑, ↑↓, →, ←	Left 2 times, Right 2 times, Down 2 times, Up 2 times, Down, Right, Left
15		→×3↓, ←, →←×3	Right 3 times, Down, Left, Right, Left 3 times
16		↑, ←, ←→, →, ↓, ↓↑, →, ↑	Up, Left 2 times, Right 2 times, Down 2 times, Up, Right, Up
⑰		←×9→×4	9 times to the left, 4 times to the right
⑱		←、↓、→、↑←、↓、→、↑←、↓、→、↑Spear attack from the left	Counter-clockwise, Left, Down, Right, Up, repeat 3 timesWhen it turns red, immediately move down

Red Attack

	Attack	Attack Pattern	Avoidance
①		Random	Move to the left or right to a spot without spears
②		Random	Move to avoid getting hit

Undyne's Date Event Walkthrough

After giving Undyne the water and ending the battle, go to Undyne's house near the Quiet Area in Waterfall and talk to Papyrus. Once you're allowed into Undyne's house and Papyrus leaves, the date event with Undyne will begin.

You Need to be Friends with Papyrus

To trigger Undyne's date event, you need to have cleared the date event with Papyrus in Snowdin. If you haven't cleared it yet, go back to Snowdin and trigger the date with Papyrus.

Conditions and Walkthrough for Undyne's Date Event

List of Boss Guides
Toriel	Papyrus	Undyne
Mettaton EX	Asgore	Flowey
Asriel	Undyne the Undying	Sans

List of Boss Characters and Order of Battles