One Punch Man, Comic Author: One, anime directed by Shingo Natsume at Madhouse and written by Tomohiro Suzuki
I really love the sucess story of one punch man as it started out as a web comic with really (pardon me) shitty drawing. But when it was done into an anime, the animators really did a great job and managed to push one punch man to one of the most popular animes even though it had only 12 episodes for its first season. It is the product of passionate artists doing their best and also, a result of web animators collaborating with each other.
Comparison of the old drawings