Mine is Berserk, it's really awesome and immersive. Also, it motivates me to work-out and live my life to the fullest. If you write your favorite manga, please add an explanation why it is your favorite.
My is also favourite Berserk. This is the best Manga ever made on MyAnimePlaylist global site have the best score.
Each page and image are the fucking masterpiece of work. Some are good at this level when you want print this (or someone paint for you) and put in on your wall in room.
This is very immersive story. As a story for me this is much more better than Witcher (I read all books and play all games)