Breather Level: Compared to the One Hit Kills in "Pteromerhanophobia", the Interface Screw of "Paedophobia", and all of "Technophobia", "Glossophobia" is significantly easier to handle due to its lack of gimmicks. As long as you can handle its strange time signature, you should be pretty much fine.
Smiler undoubtedly did an evil thing by torturing and murdering Derp. However, he wasn't in control of himself at the time, and after he realized what he did, he's incredibly remorseful and depressed because of it. Even worse, he considers Derp to be his best friend, even if Derp doesn't reciprocate.
The 2.0 update makes his situation even sadder; part of the reason he's so depressed is because he lost his beloved daughter Derpina, the only family he had before his Trollge infection, and only manages to find her one last time right before he dies. He doesn't even get a happy ending this time, either, as T_333 brings him back to life as one of many thralls he uses to torment Boyfriend.
Girlfriend's Trollge form is possibly the most popular character in the mod, both for the huge story significance and the obvious reasons.
Boyfriend's long-haired appearance in "Athazagoraphobia" has also proven to be a very popular appearance for him.
Evil Is Cool: More or less all the Trollges get this treatment but special mention goes to Legion, who's agreed by many to be a villain that manages to be horrifying, detestable and entertaining at the same time.
Even despite its silly origin, the mod is still unsettling at its best and downright horrifying at its worst, especially once you read the logs after the credits and watch MaliciousBunny's connected videos.
Similarly, Stairway looks a little silly flying in the second half of "Pteromerhanophobia" by flapping its arms up and down, but the remaining factors (the Ominous Visual Glitches, Stairway's Nightmare Face, the minor Apocalypse How in the background) keep it an incredibly climactic - and frightening - moment.
Stairway is hard to take too seriously if you remember its deeds are based on the famous Cover Yourself in Oil meme.note Although granted the meme has taken some pretty horrifying takes thanks to the "Trollge" memes.
Smiler's form during "Incident" is a Nightmare Face at its finest, but his Left animation being a silly-looking Head-and-Hip Pose helps lessen the horror a little.
"Pteromerhanophobia" introduces oil notes that instantly force the player down to 10% health. These are scattered throughout the chart rather liberally and combo devastatingly well with the axing mini-Trollges, causing this song to be a roadblock for a number of players.
The static notes in "Technophobia" are a big part of that song being under That One Level below. They're less volatile than the aforementioned oil notes, only dealing some damage rather than an insta-kill, but they're placed all over the damn place because of this, and they can wear down the health bar very quickly. This was especially bad before the 2.0.1 patch, as their hitboxes were the same size as the normal notes (much larger than such damaging notes tend to be).
"Technophobia", the player's rematch against Smiler, was created to be very hard on purpose in response to complaints that the original mod was too easy, and god damn does it deliver. The song is the second-fastest in the mod at 180 BPM (beaten only by the Optional Boss "Your Mom") and has much more frenetic charting compared to most others, as well as two incredibly long solos. Additionally, Smiler dishes out very powerful Damage Over Time on top of the mass amount of damaging static notes scattered throughout the chart, meaning you'll likely spend most of the song with very little health. It was even worse before the 2.0.1 patch, too, as the static notes had much larger hitboxes.
Turn into a Boyfriend silhouette with a Trollface that teleports between the four corners of the screen, requiring the player hover the cursor over them lest they lose health.
Become a giant spitting out projectiles that must be blocked with the cursor. This isn't very difficult on its own, but the song often cuts between it and the previous form, diverting the player's attention often, and the projectiles don't disappear when his form changes.
Summon several fast-spawning eyes in the background that the player needs to swipe the cursor over before too many of them appear.
Visual Effects of Awesome: The mod changes up the entire art style on top of using many subtle effects to support its atmosphere such as changing out character sprites and mid-song cutscenes, and it looks absolutely stunning.
Lore videos
Alternate Character Interpretation: In "How to trollge your best friend", Derp says that he has no idea who Smiler is, and Smiler replies with "But I know you." Based on Smiler also being a Well-Intentioned Extremist who just wants to help Derp smile, is he a Stalker without a Crush that Derp really doesn't know, or is he actually Derp's friend and was just unrecognizable in his Trollge form? The latter is supported by Smiler's attitude outside of his Trollge form, where he still considers Derp his dearest friend despite not being the type to stalk others.
Tear Jerker: "The first Trollge Incident" gives us some context for why Stairway is the way he is, and knowing what happened really makes his situation bleak. Having to murder a Derp-like monster for the sake of self-defense is already troubling, but notice how Stairway seems worried for the beast, asking where he is in a panic beforehand and demanding to know what happened to him, even affectionately calling him "Derpy". Stairway didn't just have to murder, he likely had to kill his best friend in self-defense, and the remorse of doing so drove him mad.
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