In Undertale Asgore first appears in the game
Undertale, serving as one of the game's antagonists. He and the monsters he ruled had been driven into the Underground, a cave beneath the fictional Mt. Ebott, millennia ago by hostile humans, and trapped there by a magical Barrier. Before the events of the game, he and his wife
Toriel had two children:
Asriel and
an adopted human. The human, who had fallen into the Underground, has the name
Chara, which when entered the game remarks as "The true name". Nonetheless, the human can be named differently by the player. Both Asriel and Chara were ultimately killed by humans following an ill-fated plan to cross the Barrier. Asgore, seeking revenge on humanity, began to reap the souls of humans who had fallen into the Underground, with the intention of using their power to destroy the Barrier. Unwilling to fully enact his plan, Asgore chose to wait and ambush them one by one rather than exit the Barrier with a single human soul and immediately claim six more. Toriel, angered by his hypocrisy, decided to live alone in the Ruins. Asgore is unseen for most of the game, though other characters, such as Toriel, warn the protagonist about him. Other monsters are more positive about him, including
Undyne, who he helped on her path to becoming the captain of the Royal Guard. Asgore also works with other characters, like
Alphys, the Royal Scientist, who helps the human get to Asgore's throne room, though warning that Asgore and the human will inevitably have to fight one another. When the human eventually meets Asgore, he is anxious to fight, doing so out of duty to the monsters rather than any personal desire to kill. During battle, he destroys the Mercy menu option on the user interface, preventing the human from sparing him and forcing them to fight to the death. Unlike other monster encounters, the player must fight him, though his health will not lower to zero upon defeat. At this point, Asgore accepts defeat, and the human can choose to either kill or spare him, having rebuilt the Mercy menu option. If spared, he will be moved, and decide to not break the Barrier, and instead become part of a family with the human, though he will accept death if killed. In the former option, the character
Flowey, who had served as an antagonist in the beginning of the game, returns and kills Asgore instead before turning to fight the human. After fighting Flowey, the player can either kill or spare Flowey as well. After the credits, Flowey instructs the player how to get the best ending. Once these conditions are fulfilled, either from reloading an earlier save or starting a new run, the human's encounter with Asgore will be interrupted by Toriel and other characters. Eventually, it is revealed that Flowey got these characters together, using their combined souls to reveal his true form, Asriel, who was resurrected as Flowey, lacking a soul, and becoming unable to feel empathy. During the fight, the human is able to rescue the souls of monsters Asriel took, including Asgore. After making Asriel stop fighting, he breaks the Barrier, allowing Asgore and the others to go outside of the Underground. In the "Genocide" route, a separate story path in which the protagonist sets out to kill all monsters in the Underground, the player is strong enough to immediately kill Asgore in one hit.
In Deltarune Asgore also appears as an NPC in
Deltarune. This parallel universe, taking place in a more standard town environment, Asgore has still gotten a divorce from Toriel, while Asriel is still alive. He was formerly the town's
chief of police, but had been fired or left for unknown reasons. He owns a
flower shop named "Flower King", a reference to his role in
Undertale. He is depicted as a loving and somewhat goofy father figure of
Kris,
Deltarune's protagonist. In Chapter 4, Asgore attempts to make amends with Toriel after a church service, but is rejected. It is later revealed that he is also employed by
Carol Holiday as a cleaner and that she is funding Asgore's flower shop. In hidden areas in the manor it is also shown that Asgore is plotting a way to clean his name and have Toriel take him back, implying a role in future chapters. It is also shown that he possesses a black shard which description matches to a shard of
The Roaring Knight's black knife, potentially suggesting a connection between the two. ==Reception==