Nice work! Equal parts psychedelic and gothic if you ask me. I think the bits of blue towards the bottom does a good job of adding variety and making sure things aren't as muddled from a distance. And on top of that, gives the rising bodies on the lower end of the piece a more undead felling. So that really ties it together a bit more on an already solid art piece.
I've made my own Halloween art for TeePublic this month too. Feels good to finally have all that out now! So I get to enjoy looking at other "festive" works at the moment.