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.
Dinosaurs, continuing the trend of dinos/sauruses being the most dangerous enemy type in the game, with high defense and attack, along with being so fast that it's nigh impossible to escape from one without jacking the game speed all the way up.
Demon worms are just as tough, and burrow underground so that you can't throw things or hurl spells at them in advance.
Good Bad Bugs: While fleeing from a monster, your speed depends on the game's current speed, but the monster's speed depends on the game's speed when it started chasing you. Thus, you can outrun anything easily by temporarily turning the game speed up.