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: Wonder Boy
The series in general
More Popular Spin-off: The Monster World sub-series. There's a reason why the PS2 compilation was titled the Monster World: Complete Collection and not the "Wonder Boy Collection"
Demonic Spiders: The frogs (which are extremely hard to hit before they jump into you) and the literal spiders that appear in droves in later stages.
Porting Disaster: The Amiga version had stumpy graphics and tinny sound, did not label shop doors, and had a small play area to fit the status border. (The Master System version instead compressed the HUD into a small bar and put the rest of the info in a pause menu, resulting in a much more playable screen size.)
Wonder Boy III: Monster Lair
Porting Disaster: The Mega Drive version had its graphics horribly mutilated, even worse music than the arcade version, and five stages were removed due to lack of ROM space.