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.
Difficult but Awesome: The game has a learning curve that looks almost like a solid wall, but it is possible to complete the game flawlessly with everything collected.
Good Bad Bugs: Normally, when you leave a level, the level resets, respawning all of its items and getting rid of any Shards or Soul Jars you've collected. Collecting a Wraithheart serves as a level exit and teleports you back to The Hub... but if the Wraitheart is one you've already collected, the level doesn't reset and it's essentially a free teleport back to the level's entrance. This is immensely helpful in collecting Shards and Wraithearts, as it lets you bypass all sorts of obstacles that would normally kill you on your way back.
Nightmare Fuel: The enemy designs. They start out pretty creepy, and then night rolls around and they get even worse.
Scrappy Level: The Citadel of Shadow. Do you like plummeting to your death on a regular basis? We hope so!
That One Sidequest: Any of the Wraitheart missions where you have to climb up the inside of a tower. You will curse the name "Model Castle" for the rest of your life. And that's not even mentioning the "sequel", Sand Castle, which you have to go through half of Model Castle just to get to. And THEN you have to do some complicated acrobatics over a bottomless pit and make a very tricky jump just to get INTO the damn place, and once you're in, it just gets harder and harder. And if you fail, at any time (which is very easy)? You have to go ALL THE WAY BACK TO TIMBERDALE (yes, Sand Castle is in Dragonreach, but the entrance to it is in Model Castle, which is in Timberdale - Guide Dang It), back through Model Castle and into the entrance again. And the worst part? This is the SECOND WORLD IN THE WHOLE GAME. And the later worlds are MUCH harder.
Wraithheart #7 in Frostblight Mills, which is hidden underneath the island and requires the Air Suit to get to. Have you mastered the Air Suit? If not, have fun constantly flying past the heart until time runs out and you fall to your death.
What Could Have Been: This beyond anything else was what this game suffered from the worst. With hints of a multiplayer mode, several Dummied Out levels, blood effects and most of the story all cut, it makes you yearn for a remake (That is if you liked the game).