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.
YMMV: Popful Mail
Demonic Spiders: Many of the enemies fought later, especially those flying knights.
That One Level: Chilly can become this, due to your lack of traction on the ice unless you get the spiked boots.
Visual Effects of Awesome: The cutscenes in the Sega CD version are sprite-based, rather than FMV. Despite this, they are very well animated, featuring tons of animation with unique poses and difficult camera angles.