I remembered playing this in 2013 and it really helped me learning vim. Then I discovered roguelike games, which depend heavily on vim key bindings, especially hjkl for movements, played a bunch of them ever since and got really fluent in vim keybindings. Now besides using vim as text editor and play roguelikes, I have vimfx extension for browsing web under Firefox and vimium for Chrome. Now I just hope I can have vim editing functionalities in any text boxes, and I have been searching for a solution for years.