For me, Death Note is a manga I've read where the anime is very much in line. The suspense and mind games are presented consistently, but with some added animations to make it more engaging.
It's quite similar. The manga and its adaptations share many core elements and storylines.
They can be quite similar, but sometimes the anime makes minor changes to fit the animation format and timing.
They're quite similar. The adaptations mostly stick to the core plot and characters of the manga.
The Demon Soayer manga and its adaptations share a basic framework, but there are definite changes. The adaptation might add new subplots or tweak the ending to create a unique viewing experience while still drawing inspiration from the manga.
Well, it requires a deep understanding of the manga's themes, characters, and storylines. The adapter needs to stay true to the core elements while adding their creative touch.
It's moderately similar. The manga has its own unique take while still drawing inspiration from the games and other forms of the franchise.
The 'reo x reo' manga is generally well-replicated in its adaptations. They capture the key elements and essence. There could be some tweaks here and there for visual or narrative purposes, but they don't stray far from the original.
For 'Naruto', the anime mostly sticks to the manga's plot. However, it sometimes extends scenes or adds flashbacks to fill the episode time. But the core story and character developments remain intact.
One of the most faithful adaptations is 'Fullmetal Alchemist: Brotherhood'. It follows the manga closely, keeping the plot and character developments intact.
The answer is no. There are a large number of light novels out there, and only a fraction of them get turned into manga. Some light novels might be too niche, or their content might not be suitable for the visual and often more mainstream - oriented manga format. Also, the process of adapting a light novel into a manga requires resources like artists, publishers willing to take the risk, etc., which means that not all light novels will end up as manga.