A different costume for Wolverine, he looks a bit grumpy - maybe he didn't get too much candy when he was trick-or-treating with it on. Clearly he was jumping on the vampire bandwagon that's gripped much of television and film but maybe he was in a werewolf-loving neighbourhood.
Not paying homage to anyone this time, just using the same style as the Maurice Sendak one, next time it'll be a different style (either my own or someone else).