Asriel Dreemurr

S POILER W ARNING : Plot details follow.

Asriel Dreemurr was a monster.

Appearance
Asriel takes the appearance of an anthropomorphic goat, similar to that of his mother and father. In his original form, he wears a striped shirt and long pants. In the form taken by Flowey, Asriel sports a pair of horns on his head, and wears a long robe with the Delta Rune on it. After using full power with the souls absorbed, Asriel gains a whole new appearance. The lower half of his body is replaced with a large narrow heart with electricity moving from side to side inside of it, a circular chest with a heart in the center, and long shoulders that have a thorny pattern. Asriel's arms seem to increase in size in this form, his forearms gaining length with hearts on them, and a long pair of wings stretching out that change color.

Personality
Through audio logs found in the True Laboratory, we learn that Asriel was a bit of a crybaby and somewhat cowardly, bending fairly easily to the whims of his adopted sibling, but otherwise was quite a kind and loving child who loved jokes and pranks.

After being accidentally remade into Flowey, Asriel lost his soul, and with it, his ability to love. Slowly driven insane by his inability to connect emotionally with anybody and the lingering influence of his malevolent sibling, Asriel became selfish and cruel, tormenting monsters and escaping the consequences with his new SAVE ability simply to escape his ennui and satisfy his curiosity. Even after regaining the ability to feel after he tricks the player into helping him absorb the souls of nearly every monster alive, he still shows a great deal of sadism and megalomania, though he remembers his true motive was not to destroy the world, but force his sibling to play with him forever, ending his boredom and loneliness. As the player saves his friends from being components of Asriel's demon form, he starts to feel ashamed of his actions and eventually surrenders, having returned to his old personality. Even after he degenerates back into a flower, he still shows elements of empathy and compassion, begging the player to not initiate a True Reset and undo all the good they have accomplished.

Main Story
After the original fallen human entered the Underground, they were taken in by Toriel and Asgore as a second child. Asriel grew to befriend this human (who is the nameable character in the beginning of the game- NOT the playable character). Through messages provided by monsters in the capital city and Asgore's home in the Pacifist Route, we learn that when the first human died. In a fit of rage and depression, Asriel took their body back to the village they came from to be laid to rest. However, the humans of the village mistakenly assumed that Asriel himself had killed the child. Through a fit of determination, Asriel was able to place the first human's body in a bed of golden flowers in the center of their home village, endure relentless attacks, and make it back to the castle underground before dying. In the True Lab, it is explained that Alphys chose the first golden flower olden flower to grow in the Underground as the recipient of some insertion, it is hinted that this was perhaps either the conscious of Asriel/the fallen human, or that the flower already possessed the mind of Asriel, and that the injection was that of determination, which brought it to sentience. This process created Flowey, which held Asriel's mind, but not his soul, or his ability to love or feel compassion.

Pacifist Route
After absorbing all six of the human souls Asgore had gathered and ambushing everyone present in the final confrontation, Flowey uses his new power to absorb the souls of all the monsters as present as well, giving him equivalent power to seven human souls and becoming the god that Asgore had planned to become. His primary use of his power was to grant himself his old form, again becoming a small child as he appeared while he was still alive; his emotions had been almost completely repressed by the flower he inhabited due to existing as a creature with a mind, but no soul. He used his incredible power to attempt to kill the only thing still standing in his way-- the player character-- and perform a massive reset, which would let him relive his entire life up to that point. However, he repeatedly referred to the player character by the name chosen at the game's beginning, which was actually the name of the first child. Asriel took a new form to combat the player character with, appearing as himself at a much older age with markings on his fur and developed horns. The player character's determination won out, but Asriel revealed he had only been using a small fraction of the power he possessed; taking another, much larger form, Asriel attacked again, but the player called out to all the trapped souls of his friends within Asriel. Restoring their memories by causing their friends to remember them despite Asriel's hold on them, the player character called out to Asriel himself, who attempted to silence him before his emotions could catch up to him. Asriel broke down, explaining that he wanted to reset because of all the loneliness he had endured and he didn't want to say goodbye to his best friend. Reverting to his childlike appearance, Asriel explained that he'd been calling the human by his old adoptive brother's name due to projecting him onto the player character, on account of the similar appearance and his own delusion. Asking for the player character's name, he confessed that he had been projecting his own kindness onto his brother, who had been a very angry child with a hatred for humanity that he would not talk about and had fallen down the mountain with dark intentions from the very beginning, and that he didn't expect forgiveness for his actions whatsoever. He used all of his power to break the barrier separating the underground from the surface, and then returned all the souls to their proper hosts; however, this evidently came at the cost of Asriel losing the form he had created for himself, as he warned that soon he would revert to being Flowey again. He returned the player character to his friends.

As the player character walks around and talks to all their friends, however, it's possible to backtrack all the way to the ruins, and the field of golden flowers that breaks the player character's fall. Asriel is there tending them, still in his childlike appearance. He says it would be better if his parents didn't know he existed, and that "someone has to take care of these flowers;" badgering him any further results in him explaining that the First Human was significantly crueler than he or anyone else implied previously, explaining his vicious outlook on life. If he is pressed further he asks if the player character has nothing better to do. After the player exists the caverns through the opened barrier and the credits run, Asriel returns as Flowey, begging the player not to reset, and to allow Frisk to live happily. It seems impossible to save Asriel from returning to his soulless form of Flowey.

Genocide Route
Even more than on Pacifist Route, Asriel - as Flowey - seems to mistake the player character as the First Human, opening about his feelings and his experiences as a flower, his incapability to feel compassion (despite spending a significant amount of time with his both parents), and how the player is the only one that understands him. He reinforces his belief of the world's kill-or-be-killed nature, up until the point where he realizes that this in no way does stop the player character from killing him, too. Now he changes his mind and begins to fear the player, even going to Asgore in desperation to warn him of the coming threat, to no avail.

Asgore is easily cut down, and Asriel, in one final attempt to save his own life, destroys his father's soul and pledges himself to the player one final time, revealing his true identity and face in the process - the one time Asriel truly makes an appearance on this route, as himself instead of a flower. His claims of being useful change into tearfully begging the player not to kill him, only to be cut down and utterly destroyed.

Trivia

 * Asriel is a biblical name that translates to "help of God" or "vow of God". In the story itself, though, his name is simply Asgore and Toriel 's mashed together, alluding to Asgore's inadequacy at choosing names.
 * Interestingly, Asriel Dreemurr is an anagram of Serial Murderer.
 * Asriel is possibly a reference to the Christian Archangel of Death, Azrael.
 * In the first half of his boss fight, it should be taken into account how the screen and his moves are colorful (and even have names!). It makes sense when you know that he died when he was a kid. (haha, kid. bc u know. hes like.... a goat. a child goat. haha.......edit this out if you will, but u know its funny........)