I liked Majora's Mask after I played it again recently. I thought that Twilight Princess was the darkest, but I've found Majora's Mask to be much more so. Everything is screwed up, and even though you may fix it, each thing you fix is reversed by the time you go back three days to fix something else.
I understand people not liking the time limit of three day, but it's interesting if you figure out the constant cycle, and I like how the characters from Majora's Mask and Ocarina are the same, showing the mirrored worlds of Hyrule and Termina.
Also, it was always great and freaky when you put on a mask that transformed you. That scared the crap out of me every time when I was younger.