Asgore Dreemurr

Lord  (/ˈæz.ɡɔɹ dɹiːmɜɹ/, AZ-gore DREE-murr ) is the ruler of the Underground and its denizens, monsters. He is the ex-husband of Toriel, the father of Asriel Dreemurr, and the second to final boss of the Neutral Route. While not necessarily evil or malicious, he serves as one of the main antagonists, scheming to kill seven humans and use their SOULs to break the Barrier that traps the monsters in the Underground.

Appearance
Asgore is a Boss Monster with broad shoulders, a blond mane and beard, and two large curving horns. He wears a suit of armor, a blue cape with yellow pauldrons, and a crown on top of his head; he also sports an intimidating stature.

Personality
Asgore is a kind and easygoing man; he attempts to be as kind as possible to the protagonist despite knowing he will ultimately have to take their SOUL. He enjoys gardening in his free time, and his favorite kind of tea is Golden Flower Tea.

Most monsters in the Underground consider Asgore to be an excellent king, despite being bad at naming things. Toriel, however, criticizes him as an indecisive and weak ruler, who prefers to keep the monsters trapped underground waiting to be saved, rather than going and taking the SOULs needed to break the Barrier on Mount Ebott.

He is an exceptional warrior, but is deeply uncomfortable with the act of killing. Asgore's inability to kill the protagonist unless their HP is 1 may be another sign of his reluctance to fight - he deliberately holds back until even his weakest attack becomes lethal.

Main Story
Before the events of Undertale, Asgore and Toriel were originally married as King and Queen of the Underground, after being cast out from the Surface after the War. They eventually had a son, Asriel, as well as a second adopted child, the first human to ever fall through the Barrier.

The tragedy of the death of both of his children drew Asgore to the conclusion that all humans were dangerous, and decided to kill any human that falls into the Underground and harvest their soul, all to gather the power needed to destroy the barrier. Toriel, appalled by his decision, divorced Asgore and abdicated her throne, and retired to live in the the Ruins, where she would care for any humans that fell through the barrier.

Before the protagonist fell into the Underground, six additional humans fell through the barrier into the ruins; Asgore eventually reaped all of their souls and kept their bodies in his castle.

Neutral Route
Asgore greets the protagonist when they arrive to the Throne Room. He comforts them as he brings them to the barrier, where he gives them a chance to turn back if they have anything left to do before the fight. Asgore does not mind the delay, admitting that he himself is not ready either.

Fighting Asgore is the only way to progress to the ending. Most characters in the game refer to him in capitals and in red or yellow text. This adds suspense to the upcoming fight, as it causes players new to the game to think that Asgore the final boss of the game.

Before fighting, Asgore tells the protagonist that it was nice knowing them. He then draws his weapon and destroys the MERCY button. Much like with Toriel, attacking Asgore when he is at low HP will deal significantly greater damage. However, he survives the attack with a small amount of health remaining and kneels in defeat, talking to the protagonist about his declaration of war against humanity, admitting that he only wanted to give the monsters hope by continuing the war, and asks them to take his SOUL.

The protagonist is given the choice of killing Asgore by selecting the FIGHT button, or sparing him by selecting the damaged MERCY button. If the protagonist had already completed a Neutral Route run beforehand, and if in that run they had killed Flowey, and chooses to spare Asgore again; Asgore begins to mention that he would care for the protagonist, but stops himself, realizing that his soul holds the key to getting the protagonist through the barrier. After telling the protagonist that it was what his son, Asriel Dreemurr, would've wanted, he sacrifices himself to give the protagonist his soul, hoping that they will find some way to free the monsters from the surface. Asgore then fades to dust, his soul remaining for a moment, only to be destroyed by Flowey, who mocks the protagonist for thinking that killing him would have made a difference.
 * If the protagonist kills Asgore, he dies smiling. Before the protagonist can take his SOUL and pass through the barrier, Flowey shatters Asgore's soul. He tells the protagonist they finally realized that this is a 'kill-or-be-killed' world.
 * If Asgore is spared, Asgore is surprised that the protagonist would choose to remain in the Underground, and offers to take care of the them. Flowey appears and finishes Asgore off, both body and soul. He then mocks the protagonist that they still failed to learn that this is a 'kill-or-be-killed' world.

Either way, Flowey steals the six human souls that were revealed prior to the fight. The protagonist deals with Flowey, passes through the barrier, and exits the underground alone. Asgore's death has a serious impact on the monsters.

True Pacifist Route
When combat with Asgore begins, it is interrupted by Toriel, who states how awful it is that he could seek to hurt an innocent creature such as the protagonist. After that, Undyne, Alphys, Papyrus, and Sans arrive and begin conversing, until Flowey appears.

During the fight against Asriel, Asgore appears as one of the Lost Souls. After the fight, he can be seen in the epilogue, asking the protagonist if they would become the ambassador for monsters to humanity on the surface. He also appears during the True Pacifist Ending Credits, trimming a hedge to the shape of Papyrus's face in front of Toriel's new school.

Genocide Route
When the protagonist reaches the throne room, Asgore, who was told by Flowey about their arrival, doesn't recognize the protagonist as a human, asking them what kind of monster they are. The protagonist initiates combat and depletes his entire health bar with a single blow. Flowey returns to land the final hit and destroys his soul.

In Battle

 * See Asgore Dreemurr/In Battle

Toriel
Toriel is Asgore's ex-wife. Asgore wishes to befriend Toriel, but she refuses his advances. Before they separated, they used to be "insufferable together, nuzzling noses, bein' all cute n' cuddly", as described by Gerson. The two ultimately fell apart after the deaths of their children.

In addition to general moral objections to war, Toriel is generally disgusted by Asgore's decision making; despite having the resources to solve the problem immediately and peacefully, he instead chose to keep the underground in despair, meekly hoping another human never comes.

After Toriel's departure, it seems that Asgore greatly missed her presence; a "Room over renovations" sign is put on her room in Asgore's Home, and multiple crumpled up pie recipes imply that Asgore attempted to recreate the way her pies tasted - though he could never truly replicate it. This is further supported by his reaction to the protagonist eating Toriel's cinnamon-butterscotch pie during the fight.

In the True Pacifist ending, Asgore can be seen trimming the bushes in front of Toriel's school. It is unknown if they have worked things out and gotten back together, or just remain as friends.

Undyne
When Undyne was younger, she met Asgore in person and challenged him to fight. After Asgore defeated Undyne several times, he offered to train her. When she finally knocked him down, Asgore was very happy, much to the surprise of Undyne. Asgore kept training Undyne until she became the head of the Royal Guard.

Undyne has knowledge of Asgore's favorite type of tea, and the fact that he often gets marshmallows stuck in his beard when he drinks hot cocoa, implying that he often visits her home.

Asriel
Asriel was Asgore's biological son. Asgore loved him dearly, equally as much as he did the first human.

Trivia

 * Dreemurr is an anagram of murderer.
 * His full name is an anagram of "Sage or Murderer".
 * In addition, when pronounced, "Dreemurr" sounds like "dreamer".
 * When attempting to name the Fallen Child "Asgore", the game replies "You cannot." and forces the player to go back.
 * During Asgore's Boss battle, he conceals his face by looking downward, showing his reluctance to fight.
 * It is possible that Asgore is the Santa of the Underground that leaves presents under the tree in Snowdin.
 * Asgore cannot die of age, as he is a Boss Monster, and his son is dead.
 * Asgore may have a little bit of knowledge or memories of other timelines.
 * In the neutral route boss fight, Asgore remains aware of killing the protagonist even after reloading, much like Sans or Flowey. If Asgore kills the player, and they die or reload the game, if the player select "Talk" in the "Act" menu, the protagonist tells him how many times he has killed them and Asgore nods sadly.
 * At the end of the True Pacifist Route, when SAVING the Lost Souls, the ACTs for Asgore's soul are references to the boss battle in the Neutral Route (Mercy, Stare, Talk) which technically never took place in that timeline. They're effective anyway.