Asgore Dreemurr

King Asgore Dreemurr is the ruler of the Underground and its denizens, animals. He is the ex-husband of Toriel, father of Asriel Dreemurr, adoptive father of the first human, and the penultimate boss of the Neutral Route. While not evil or malicious, he serves as one of the main antagonists, planning to kill seven humans and use their SOULs to break the barrier which traps the animals in the Underground.

Appearance
Asgore is a Boss Animal with broad shoulders, a golden blond beard, and two large curved mountain goat horns. He wears a suit of armor, a purple cape with golden pauldrons, and a crown on top of his head; he also sports a bulky stature. The weapon he uses in battle is a long, red trident adorned with a flower.

Personality
Asgore is a kind mountain goat that enjoys gardening, Golden Flower Tea, and Toriel's Butterscotch Pie. Like his son, he speaks in southern slang. Before his battle, he offers the protagonist many opportunities to explore the Underground and is reluctant to fight them at all; he even suggests that Toriel, the protagonist and himself live as a family if the protagonist spares him.

Monsters in the Underground look to Asgore for hope, and his plan to collect seven human SOULs is one of the few things that keep them going. However, Asgore does not want to kill anybody and feels so guilty that he offers the protagonist his SOUL to "leave this cursed place." Though he is miserable because he has killed humans, he feels that it is his duty to his people to battle the protagonist.

Asgore lives in the past and wants nothing more than to see his wife and child again, even though they have been gone for a long time. He reiterates the same phrase in his journal every day, perhaps in denial that life has changed since Asriel's demise.

Animals also note that he is bad at naming places and names locations, the names being quite literal (such as naming the animal's first home in the Underground "Home", and naming their new home "New Home"), and Gerson suggests this may be because Asgore is not the most intellectual animal, with the smarter member of the royal family as well as the one which was actually running the city being Toriel.

Main Story
King Asgore and Queen Toriel ruled the Underground for millennia after humans sealed the animals Underground upon their defeat during the war. Toriel and Asgore later had an emperor penguin chick as a son, Asriel, and adopted the first human to fall into the Desert.

The tragedy of his children's deaths led Asgore to declare war on humanity in a fit of anger. He swore to kill any human that fell into the Underground and planned to use their SOULs to break the barrier and destroy all humans. Toriel, disgusted with him, left New Home and returned to the Desert.

Before the protagonist fell into the Underground, six more humans fell. They all died, and Asgore saved their SOULs for future use.

Neutral Route
Asgore greets the protagonist when she arrives in the Throne Room, where he was watering flowers. He comforts her as he brings her to the barrier, giving her a chance to turn back if she has anything left to do before the fight. Asgore does not mind the delay, admitting that he 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.

Before fighting, Asgore tells the protagonist that it was nice knowing her. He then draws his trident and destroys the MERCY button, possibly to weaken the protagonist, worsening her chances of winning and preventing the protagonist from sparing him and shattering the hope of animals. Much like with Toriel, attacking Asgore when he is at low HP deals 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 animals hope by continuing the war, and asking her to take his SOUL.

The protagonist is given the choice of killing Asgore by selecting the FIGHT button or sparing him by choosing the partially repaired MERCY button. Either way, Flowey steals the six human souls that Asgore reveals before the fight and closes the game. The protagonist proceeds to deal with Flowey; after Flowey's defeat, the protagonist leaves the Underground. Asgore's death has a grave impact on the animals.
 * 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 she 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 her. Flowey appears and finishes Asgore off, both body and soul. He then mocks the protagonist that she still failed to learn that this is a "kill-or-be-killed" world.
 * If the protagonist has already completed a Neutral Route run beforehand, and in that run 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 have wanted, he sacrifices himself to give the protagonist his soul, hoping that she finds some way to free the animals 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.

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. This uses the same text and hit as when she interrupts Flowey at the beginning of the game. She then explains that she interrupted to prevent both Asgore and the protagonist from killing each other. While Asgore is ecstatic to see Toriel again, he is saddened when she chastises him for his plan to collect souls, arguing that he could've gone through the Barrier after collecting one soul, but instead chose to wait and hope another human never came. 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 alongside Toriel. After the fight, he is then seen in the epilogue, where he is first available for a conversation along with the other main characters, and later asks the protagonist if she would become the ambassador for animals to humanity on the surface. Asgore also appears during the True Pacifist Ending Credits, trim-eating 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 her arrival, doesn't recognize the protagonist as a human, asking them what kind of animal she is. The protagonist forcefully initiates combat and depletes his entire health bar with a single blow. Flowey then returns to land the final hit and destroys his SOUL.

Toriel
Toriel is Asgore's ex-wife. Before they separated, they used to be "insufferable together, nuzzling noses, bein' all funny n' goatee," as described by Gerson. The two ultimately fell apart after the deaths of their children and Asgore's declaration of war on humanity.

After Toriel's departure, it seems that Asgore greatly missed her presence. A "Room under renovations" sign is put on her room door 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 the inverse of Toriel continuously making her pie and only having low-maintenance plants in her home. This is further supported by his reaction to the protagonist eating Toriel's butterscotch-cinnamon pie during Asgore's battle. After being defeated, he tells the protagonist he just wants to see his wife and child again.

When Toriel interrupts the battle between Asgore and the protagonist, she chastises him for his plan to collect human souls and even turns him down when he asks her if they can be friends again, which makes him sorrowful. However, after the fight against Asriel, where their souls are saved as one, her aggression towards him seems to cool down.

In the True Pacifist Ending, Asgore can be seen trim-eating the bushes in front of Toriel's school.

Undyne
When Undyne was younger, she met Asgore in person and challenged him to fight. After Asgore defeats her by dodging all her blows, refusing to land his own, he offers to train her. When she finally knocked him down, Asgore was overjoyed, 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. Asriel's habit of using words such as "howdy" and "golly" likely came from his father, as did, potentially, his lack of naming skills, having dubbed his vulture form "Flowey."

Molly
Molly was Asgore's adoptive daughter, whom he loved just as much as Asriel. It is implied Molly made the "Mr. Dad Guy" sweater for Asgore. Asgore considered Molly "The future of humans and animals," as is repeated in the Game Over text and VHS tape of Molly's death. He may even have believed them to be the Angel of the prophecy, as he also states he thinks the protagonist is the Angel immediately after noting they and Molly have "The same feeling of hope in [her] eyes." In the Genocide Route, Flowey states that despite him trying "hundreds of ways" to get Asgore to show him the human souls, and never succeeding, "Molly... I know he'll do it for YOU."

Trivia

 * When attempting to name the fallen child "Asgore," the response becomes "You cannot." and prevents the name from being used.
 * It is possible that Asgore is the Santa Claus of the Underground that leaves presents under the palm tree in Sanddin.
 * Asgore cannot age until his child has grown up to 63 years older in appearance and actual age than the parent. However, since Asgore's son, Asriel, is dead, Asgore cannot age.
 * Asgore is the only goat that drinks tea.