The video game sprung up from seemingly out of nowhere in the summer of 2015, and since then it's gathered what feels like millions of fans. Garnering controversy all over the Internet in discussions about its merit as a game, taking up hundreds of threads and topic discussions on theories and mysteries in the game, and sparking both sobs and laughs through its heavily user-choice-influenced storyline, "Undertale" by Toby Fox has brought to life what may be a classic for the decades.

Throughout various runs, I've noticed some of the game's most shocking, potentially tragic moments and have listed them below (in no particular order - I could never rank which ones moved me more!). Spoilers ahead for every path follow; beware!

1. Undyne's death in a Neutral Run

The game almost punishes you for going the middle route: you either free and save everyone, or you kill everyone without any hesitation. Undyne's death in the Neutral Run is arguably more tragic than its mirror in a No Mercy run; in the No Mercy run, Undyne's determination comes into form at the very beginning, and the rest of the fight is simple for her character (even if it may be difficult for the player). However, in Neutral... when you finally get the drop on the aquatic heroine, she refuses to die.

You continue striking her and watching her crumble apart. Literally. First, her limbs turn to dust; slowly, the rest of her body joins the mess of pixels that is her body's disintegration. You keep on striking her, and she keeps on clinging onto life. Her attacks get slower, her words even more desperate as she denies she's going to meet her end at your hands. Finally, she melts in front of your character, still vehemently denying she will die like this.

I have yet to confirm if you can spare her at that point, but... if I know Toby Fox, I would say that there is no going back once you've gotten her down to the last stage of her fight. He makes sure we finish what we start (especially when it comes to Mettaton NEO, who is a different story altogether).

2. Asgore's death at the end of a Neutral Run

King Asgore was always a tragic character. Due to circumstances he couldn't control, he lost both his children in one night. Because of his subsequent anger, he lost his wife permanently. Because of his decree in the heat of the moment, he is forced to engage in battle with you, a battle he doesn't truly want to have. When you spare him at the end of your Neutral fight with him, he is overflowing in gratitude and almost desperate relief: he gushes about having a chance at a family again. He dreams of being back at his queen's side, with his children back at his side. He wants another chance at the life he spoiled.

Of course his hope is for naught. Flowey comes back right when Asgore begins to look happy once more and ends the life of the king. (Flowey's entire character is completely tragic as well, in my opinion.) No one sees it coming. You haven't seen Flowey in ages, and while both you and Asgore are both caught up in the hope and prospect of happiness for him... suddenly Flowey's attacks appear and end the king's life completely.

3. Sans's death at the end of a No Mercy Run

Sans's last words may be the ones that captured my breath and made me wish to cry the most (which is why I also used fanart for this particular point - the poignancy isn't captured in-game, after all). At the end of practically the most difficult fight in the entire game, at the end of a long No Mercy run in which you killed literally everyone, you finally catch Sans off-guard and land a lethal blow on him.

He sinks to the floor, blood pouring out of his chest and mouth. He then gets up with his wearied smile, and he dismisses his own death and the entire situation as a whole. He denies everything at his last moments. "Welp, I'm going to Grillby's." He knew you'd long killed everyone you could in Snowdin, and Grillby's is completely deserted, survivors fleeing elsewhere. He moves off-screen, and you can't even see him when he finally goes, which he does only after...

... speaking to his dead brother. The one you killed in the beginning of the game. Papyrus had been trying to spare you, to see if you wouldn't kill him, but then you took advantage of his mercy to end his life easily. "Papyrus, do you want anything?" Sans's brother is dead, and he knows this, but right before he dies, right before you hear his body turn to dust, instead of seeing it like every other big boss, Sans is living in a world where he is still okay, and everyone he loves is still alive.

Of all the ways I enjoyed being a bloodthirsty psychopathic killer in my No Mercy runs, these moments with Sans killed me inside.

4. Asriel at the end of a Pacifist Run

Asriel Dreemurr, also known as Flowey, the son of Asgore and Toriel who kind of half-died, is someone Toby Fox sets up as the villain throughout the entire game. But when you finally traipse through all of the story and learn everything about your character, the Dreemurr family, and the past of the monsters in the underground and their interactions with the humans... Asriel's speeches at the end are only heart-rending.

He admits he only took on the evil role because it was the only way you would pay attention to him. He cries out about how lonely and painful his life has been ever since your character (rather, the character your character represents) has been gone. When you continuously spare him, he grows even more desperate and begins to wail; in a meta-game manner that only Undertale could accomplish gracefully, he knows you'll leave if you beat him and you won't "play with him" anymore. He sheds actual tears when he tries to kill you repeatedly so you will keep on restarting to begin a battle with him anew ("Just stop and let me win already!"). Everything he did was to become noticed by you because he loved you before you were lost from his life. It's honestly moving and perhaps one of the most relatable moments of the game.

And later, when he redeems himself and breaks the barrier between the monster and human world? He knows it won't be long before he turns back into Flowey. He uses his last living moments as himself to undo as much of the evil he'd done as Flowey as he could. If you encounter him right before you leave, he asks you to please forget about him and let him be, and to remember him as Asriel, not as Flowey. We all wish for a better end for Asriel by the end.

5. Flowey's growing fear for you at the end of a No Mercy Run

On the complete flip side of the above point, when Flowey finally breaks underneath your acts and personality during a No Mercy Run, it's honestly gruesomely shocking how much his character changes. The villain who told you "It's kill or be killed" at the beginning of almost every new game you started? The one who manipulates and watches you from the shadows, laughing at all your efforts and taking pleasure in killing you over and over again during a Neutral Run Omega Flowey fight? Suddenly, he's realizing the position you two are in. He feels, for the first time, true fear.

He begs you not to kill him. He cries about it. He does absurd things to win over your trust, to show to you how useful he can be. His entire philosophy changes when the positions of power are switched, and you can pinpoint the exact moment he realizes he cared for you a lot more than you cared for him, and that you're going to wind up killing him, too. It's almost painful to watch.

6. Chara's possession of Frisk at the end of a Soulless Pacifist Run

So let's say you play No Mercy first before you play any Pacifist or Neutral runs. If you agree to the bloodthirsty Chara's demands to erase the world you two have killed everyone in first, you are rewarded with a blank screen for ten entire minutes. (The other option to disagree also results in a shock, holy crap.) You have literally erased all of Undertale. If you agree to give Frisk's soul in order to restore the game to play again, that means you will never be able to do a True Pacifist run, ever.

You can certainly try a Pacifist Run. You can do everything right, but at the very end, Chara does not forget Frisk's soul belongs to them. Even if you get a happy ending, you will be rewarded at the very end of the credits and the epilogue showing all the monsters getting along fine in the human world... plus a scene at the end with Chara taking over Frisk's body to wreak havoc on the new world.

Unless you uninstall and reinstall the game, no True Reset will ever be rid of this exchange of souls. There will be a permanent flag in the game that Frisk's soul belongs to Chara, if you allow this to happen. Throughout the fanbase, this Soulless Pacifist ending is known as "the worst possible ending."