History YMMV / Undertale

*** '''Where are the knives.'''

* GuideDangIt: Defeating Undyne nonviolently. She has a couple of ACT options - one to make her attacks harder, one to make them easier. Enduring enough of her attacks causes her to slow down and grow weaker, as well as praising your strength. [[spoiler:Defeating her gives her a brief moment of HeroicWillpower... before she dies anyway.]] So what's the way to spare her? [[spoiler:You have to run away from the fight instead of bothering with any of that.]]

* ParanoiaFuel: [[spoiler: Flowey knows about your instruction manual. Flowey knows what you did... and he'll leave a message to let you know it. Flowey also knows when you save scum and when you stick your nose where it isn't wanted (the website source code). You can't hide. Hee hee...]]
** In-game, try to walk a screen or so into a room (such as the first save room), then walk back to its entrance. [[spoiler:You might see a spying Flowey quickly running out of the room.]]
* PlayerPunch: [[spoiler: Killing Toriel.]]
** Even more so than that, [[spoiler: killing her, then going back to save her. Flowey knows what you did.]]
** Enjoy being an aloof [[HundredPercentCompletion completionist]] and seeing every possible route? Well, then, if you [[spoiler:save Toriel]] on your first runthrough, you'll have to go back and [[spoiler:kill her]] to see what happens, won't you? After all, it's not like it's something you'd ''actually'' do, you just want to see everything. [[spoiler:Nice try. Once again, Flowey knows what you did.]]

** There are quite a few gems if you take the most cruel route during gameplay:

* FridgeBrilliance: "Every time this old tree grows leaves, they fall right off." [[spoiler:It's FiveSecondForeshadowing of what Toriel reveals shortly before the fight with her.]]
* FridgeHorror: One post from Flowey on the Twitter page winds up CrossingTheLineTwice after you've played the game:
-->''Strive every day to increase your "LOVE." Remember, "LOVE" comes easiest from friends and family. =)''

* CrossingTheLineTwice: One post from Flowy on the Twitter page:
-->Strive every day to increase your "[[CharacterLevel LOVE]]." Remember, "LOVE" [[BackStab comes easiest from friends and family.]] =)
* CrowningMusicOfAwesome: Listen to it [[http://tobyfox.bandcamp.com/album/undertale-demo-ost here!]]
** Particularly notable is the BattleThemeMusic for [[spoiler:[[BossBattle Toriel]]]], "[[http://tobyfox.bandcamp.com/track/heartache Heartache]]". It combines [[{{Retraux}} the simplistic chiptune style]] of most of the game's tracks with a more modern, grandoise theme.

* FridgeHorror: See CrossingTheLineTwice, above.

** [[spoiler: Flowey]]'s "[[NightmareFace funny faces]]".
** There is exactly [[KillEmAll one route]] where [[spoiler:Flowey]] will ''not'' give you a HannibalLecture at the end. What he says instead is [[YourApprovalFillsMeWithShame quite possibly the most chilling thing in the entire game]]:

** ''Where are the knives.''
** ''[[InterfaceScrew That was fun. Let's finish the job.]]''

--->"Hahaha... You're not really human, are you? No. [[CompleteMonster You're empty inside]]. [[NotSoDifferent Just like me.]]"

** Particularly notable is the BattleThemeMusic for [[spoiler:[[BossBattle Toriel]]]], "[[http://tobyfox.bandcamp.com/track/heartache Heartache]]". It combines [[{{Retraux}} the simplistic chiptune style]] of most of the game's tracks with a more modern, grandoise melody.

** Enjoy being an aloof [[HundredPercentCompletion completionist]] and seeing every possible route? [[spoiler:Save Toriel the first time, then go back and kill her just to see what happens. Once again, Flowey knows what you did.]]

--->"Hahaha... You're not really human, are you? No. You're empty inside. [[NotSoDifferent Just like me.]]"

* CrowningMusicOfAwesome: The BattleThemeMusic for [[spoiler:[[BossBattle Toriel]]]], "[[http://tobyfox.bandcamp.com/track/heartache Heartache]]".

* NightmareFuel: [[spoiler: Flowey's "funny faces".]]

* NightmareFuel: [[spoiler: Flowey's "funny faces".]]

-->Strive every day to increase your "[[CharacterLevel: LOVE.]]" Remember, "LOVE" [[Backstab: comes easiest from friends and family.]] =)
** The FridgeHorror comes when you realise LOVE in this game means Level and you can get it by [[CainAndAbel killing things]].

-->Strive every day to increase your [[CharacterLevel: "LOVE."]] Remember, [[Backstab "LOVE" comes easiest from friends and family.]] =)

-->Strive every day to increase your [[CharacterLevel‎ "LOVE."]] Remember, [[Backstab "LOVE" comes easiest from friends and family.]] =)

** In-game, try to walk a screen or so into a room (such as the first save room), then walk back to its entrance. [[spoiler:You might see a spying Flowey quickly running out of the room.]]

* NightmareFuel: [[spoiler: Flowey's "funny faces".]]

* HotMom: Toriel is seen as a MILF among some furries.

* NightmareFuel: [[spoiler: Flowey's "funny faces".]]

** Even more so than that, [[spoiler: killing her, then going back to save her. Flowey knows what you did.]]