Undertale

Summary
You play the game as Frisk, I child who used to live on Earth. You fall into the monster world after a war has occurred, they need 7 human souls to get out, they already got 6, you then decide between the 3 routes, pacifist (you don’t kill anyone, you free monsters and they befriend humans again) neutral (you simply escape and kill some monsters) and genocide (you kill all monsters, and escape) all these playstyles can affect your next playthrough.

Gameplay
There are three main ways to play Undertale, which are called routes. Neutral, total pacifist, and complete genocide.

Neutral Route
In the neutral route, you can treat creatures however you want. You can kill and spare whoever you want. Neutral is the easiest route, and therefore the best for beginners. You can easily farm experience points off of the smaller enemies, and spare the bosses to avoid getting killed.

Pacifist Route
In order to play pacifist route, you must spare every single character in the game. Pacifist is easily the hardest route. Almost everyone is challenging, mainly because you have 20 HP the whole game. Sometimes you can make a mistake and then suddenly, you're playing the neutral route.

Warning: This section contains spoilers!!!

In the pacifist route you first meet toriel. She takes you to her house and teaches you some of the puzzle mechanics of the game. Then you fight her, first she’ll be playing as a normal monster would, but eventually you’ll be able to one hit kill her and she will move out her fireballs, you then have to click spare multiple times, then she’ll leave you. Then you start walking and meet sans, he takes through snowdin (toriel lives in the “ruins”, where there is a door to go to the actual underworld). You meet papyrus and fight him. He will keep beating you until he asks you if you want to be spared, they if you say yes, you’ll be friends and have a date with him, if you say no, you just keep fighting until he asks again. Then you have a date with him that will let you unlock the first part of the pacifist route (if you don’t do these “story parts” at the end either way asgore will die, but if you spared him and flowey kills him he gives you a clue to do the pacifist route). You go to the waterfalls and meet monster kid, a monster that admires undyne, the main guardian of asgore. She wants to kill you so monsters can escape. In her boss fight you run to the “hotlands” and she starts to melt. You give her water, then go back to the waterfalls and befriend her. In the hotlands you meet alphys, the royal scientist who is in love with undyne. She helps you beat her creation “mettaton” that wanted to use you in its show. You beat her and help alphys tell undyne she loves her. You go to the true lab and alphys explains what flowey is and what determination is. Right before asgore, you meet Sans. He will judge you for how many monsters you have killed, but in the pacifist run you’ll have none. You go to asgore, who is nice, but he wants to kill you to free monsters. Right when he starts (if you did all the befriending parts) toriel will stop him just like she stopped flowey, then flowey catches you and all monsters, and turns into Asriel. You befriend him and he recovers his conscience, then you all escape and live on the surface with the humans in harmony.

Genocide Route
In the genocide route, you must kill every single creature in the game. Genocide has the hardest bosses. While there aren't very many, the bosses that you fight are extremely hard. You need a lot of practice to play genocide. Genocide is very easy to mess up, so if you are very committed, be careful and patient. During the final boss battle in genocide, the player must face Sans, a skeleton with strange powers. In this battle, if you check his stats, they will tell you that he is the easiest boss in the game. This is a deception, as Sans is actually the hardest boss in the game. During this battle, the famous song MEGALOVANIA is played.

Backstory
Undertale stars a human, who fell into the underground, exploring the lands below. Each route in the game tells a different story with a different ending. The story that occurs in the 3 routes is the story of how once monsters and human lived in harmony, but humans fell threatened due to the ability of absorbing souls that monsters posses. A war occurred, and humans used magic to trap all monsters behind a barrier that took 7 human souls to destroy. One day, Chara, fell into the underground and seemed nice. Toriel and Asgore adopted her, and she became friends with their son, Asriel. Chara told Asriel to kill her in order to go outside. Chara told her that it was because Asriel told humans monsters were good. A monster needs a human soul to pass the barrier to the human world since the human souls are much more powerful since they have more “determination,” but Chara’s actual intention was to control Asriel and kill many people. She couldn’t control him and humans didn’t understand Asriel, so they killed him on top of some yellow flowers. After this, Asgore declared that any human who fell into the underground would be killed. Toriel divorced because she did not like this. Time passed, and Asgore got 6 souls, then frisk falls into the underground. Gonna explain how it connects. Somehow, when you go though the genocide route, you turn into chara or have her persona, it isn’t explained but it could be that you’re correlating your evil actions to being chara. Asriel died in some yellow flowers, this made that when alphys put determination in a plant flowey was born, he’s asriel but without a conscience and he enjoys torturing monsters, this causes the whole plot. Asgore got 6 souls and that meant that there was only 1 left in order to break the barrier that goes to the human world, that making it even more important to gain your soul. This also causes the divorce of toriel, ending with her living in the ruins to save kids from going into the underground (the area where most monsters live) (the ruins is what’s in front of the whole where kids fall in) that makes you meet her at the beggining, and did not allow you to go to the underground, because she had seen other kids do it and die.

Summary
Undertale was created by Toby Fox. He made the game almost entirely by himself, with help of a person only known as Temmie in the credits. Toby made the plot, the music, and many other parts of the game. Temmie had a bunch of character designs and helped with character development. '''Elaborate. I know nothing about this.'''

Earthbound: The Halloween Hack
Toby Fox was a huge Earthbound fan. He created a hack for Earthbound called Earthbound: The Halloween Hack. In Earthbound, a scientist (name?) sends Ness and his friends to stop (what's the antagonist's name in Earthbound?) via a time machine he had created. Earthbound: The Halloween Hack, is a post Earthbound world, in which Ness and his friends don't return. The scientist (name) is tormented by the fact that he caused the death of these children.

This hack inspired Toby Fox to create his own RPG known as Undertale.

Random Development Stuff
'''This section needs some help. '''

Super Smash Bros. Ultimate
One day, Masahiro Sakurai, the creator of the Super Smash Bros. series, invited Toby Fox, a long with many other video game creators, to his house for a Super Smash Bros. tournament. He stated that the winner of the tournament would get a character from their game put into Super Smash Bros. Ultimate as a playable character. Toby Fox won the tournament, thus earning Sans his place in Super Smash Bros. Ultimate. Sans became a premium Mii Gunner costume, along with a remix of MEGALOVANIA by none other than Toby Fox himself.

Trivia

 * Toby fox is the creator of Deltarune as well. The inspiration for Undertale actually came from the development of Deltarune.
 * Toby fox can be seen composing songs in other games too, like the most recent one: Pokemon Sword and Shield, with the song Battle! (battle tower trainer)