I'm just back from watching the '84 movie "The Neverending Story" at my local cinema and man this movie is so good, and I have to say it is really worth it to watch it at the cinema. With the great sound rumbly bass and big screen it really is something special.
And the scene with Artax in the Swamp Of Sadness, it is such a good scene, it got me back then when I saw it the first time in the cinema when I was seven, I was in the middle of the swamp of sadness, so sad myself that I could feel myself sinking together with the horse. Same feeling today, such a good scene.
But you can't just watch the scene you have to watch how the movie portraits the friendship between Artax and Atreyu, and then loosing such a good friend to sadness/depression, this is some fucked up shit. I heard that in the book Artax speaks and you get to know why he is so sad.