These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Awesome Music: The music when you first arrive on 24 Carrot definitely fits.
The tune when the four new owners of Poptropica transform into a massive robot.
The music whenever you arrive in the beautiful 1950s town at Monster Carnival Island.
Recently, the video on Virus Hunter Island shows what the Virus can do. It's terrifying and disturbing. The virus can infect whole organs and eventually the whole body. Soon, the infected can infect everyone else. The scariest part is that it mentions that the virus can easily make everyone extinct. The creepy music does not help either.
MONSTER. CARNIVAL. ISLAND.
Whatever happened in the Bad Future in Time Tangled Island is never explained. But judging from the terrifying damage and the fact your character, now 50 years old, is the sole survivor, something happened.
That One Boss: Pretty much every boss could count. However, just mention the name "Mordred" and people will start foaming at the mouth.
Zeus from Mythology Land may qualify.
That One Level: Greg's Twisted Wizard game on Wimpy Wonderland Island. The ogres are fast,attack in numbers, attack from all directions, and you WILL die if your walls aren't strong enough to hold them off while you kill them with lightning. And God help you if your thunderbolts miss even one of them. Oh, did I mention you only have one life, instead of three, which means that if an ogre gets you even once, you have to start over? And if your inner defenses break down, the ogres become even faster than they already are? Have fun.
Snoopy's Piano challenge on Great Pumpkin, the dots fall too far apart, the piano keys are too close together, and when dots are close together they fall in-between the black and white keys, which are stupidly close together, the bar instanly drops all the way if you miss the first dot and Snoopy makes annoying pained expressions if you are losing making the mini-game harder than several boss battles.
Three words: Astro Knights Island. So hard the developers released an official, in game walkthrough for it because it was the Island with the lowest rate of completion.
The ridiculously hard Dryads level on Twisted Thicket. You have to shake the mouse, but it won't scare all of them away. Countless players have tried to shake them off, only to be carried off into the sky repeatedly.
The Scrappy: If comments on Vampire's Curse Island tutorial videos are anything to go by, Christopher isn't very well-liked. Also, almost everyone despises Zeus.
Surprise Difficulty: Just controlling your character can be challenging at times, and several islands require precise platforming, puzzles, and timing.
Unfortunate Name: An example of one of the horrible names you can have is "Lazy Eye." Also "Creepy Gamer."