Undyne/In Battle

Undyne is a weapon-based opponent, wielding a spear to change the protagonist's SOUL mode while using multiple spear patterns and combinations to attack.

Soul modes
Green Mode is used initially, with the red mode being used twice briefly, and then exclusively following the last set of attacks in green mode.

Patterns

 * Note: All damages assume no armor, neutral or true pacifist route, and LV 1. In the genocide route, these attacks deal 8-12 damage.


 * Green Soul
 * She throws arrows from all sides at the protagonist in green mode, including specifically slow and fast moving arrows, as well as arrows that flip the orientation that they are approaching from. These attacks do 5 damage per hit.


 * Red Soul
 * She restricts the Bullet Board to a minuscule box which launches spears upwards toward the protagonist in three columns. This attack has a pixel-perfect safe spot between the left and center spears. This attack does 5 damage per hit.
 * She also throws a volley of continuous spears at the protagonist on a larger Board. This attack does 5 damage per hit.
 * After changing the soul mode to red at the end of an attack in green mode, she will throw a single spear at the protagonist. This attack does 4 damage per hit.
 * She throws rings of spears which enclose on the protagonist while rotating. She has another version of this attack in which the spears do not rotate, but instead head straight towards the protagonist's soul; the spears travel in the direction they were initially facing for a few seconds before fading away. These attacks are Genocide Route exclusive.

Strategy
To spare Undyne, the protagonist must deflect her spears while in Green Mode and flee from her while in Red Mode (it is not possible to escape in Green Mode) and run through the cave she was guarding. After completing three green phases, she will switch the protagonist to Red Mode while throwing a spear which can be dodged by moving up or down. Once in Red Mode, the protagonist can escape. She will chase the protagonist down, and due to her fast speed will catch up with them until they have endured at least three volleys, each one harder than the last. Undyne the Undying, however, cannot be spared.

If the protagonist does not escape while in Red Mode, Undyne will throw more spears and then switch them back to Green Mode for another three-turn volley. Fleeing from her as soon as possible makes the battle significantly easier than trying to weather her first three volleys in one go, as she progressively increases her projectile speed over the course of the fight, while fleeing resets the speed. If the protagonist does not flee, Undyne will not stop attacking, and the speed of her attacks will continue to increase. The protagonist can also escape back the way they came from, although it takes two battles to do so as she spawns right behind the protagonist.

If the protagonist reaches Hotland, Undyne will stop for a moment to scold Sans for falling asleep, allowing the protagonist to outrun her. The protagonist must then run across a bridge until they reach an area with a water container. Then, Undyne will slowly try to reach them, but she will collapse and faint due to the high heat, and will no longer attack. At this point the protagonist can either keep walking or pour water on her, letting her leave and making the Undyne date available on the Pacifist Route.

Mechanics
If Undyne's health reaches 0, she manages to cling on to life with Determination and survives further attacks from the protagonist. The protagonist's SOUL returns to Green Mode as Undyne continues attacking; the arrows move slower each turn. After several turns when this occurs, Undyne begins to ripple, her body starts to split apart. She reforms due to her Determination, causing her to have more Determination than her monster body can handle. Because of this, she melts (similar to the Amalgamates in the True Lab at the end of the True Pacifist Route) and slowly passes away.

Trivia

 * Undyne's dialogue ("You're going to have to try harder than that!") in the Neutral Route after draining all her HP is similar to her final sentence when transforming into Undyne the Undying, just before she fights the protagonist ("You're gonna have to try a little harder than THAT.").
 * It is the one line of dialogue that is always uttered when Undyne is about to die, implying the Determination within is what makes her taunt the protagonist as she refuses to die or give up.
 * When you can kill Undyne with one more hit, choosing spare still kills Undyne.

Undyne/Im Kampf ‎‎Undyne/En Combat ‎Undyne/W walce Андайн/В бою Undyne/戰鬥中