Von Miller hosted his annual All Hallows' Eve bash for his teammates on Monday ... and the unofficial theme seemed to be people who famously dabbled in the booger sugar, nose candy, devil's candy ... you know, COCAINE!

Check out linebacker Brandon Marshall who transformed into Bobby Brown, complete with a gold chain and king-sized bag of yayo.

Wide receiver Emmanuel Sanders rubbed white powder all over his face to become the legendary "Chappelle's Show" crackhead Tyrone Biggums.

And, not to beat a dead (white) horse ... O.T. Genasis was there performing his drug-inspired anthem, "Coco."

Oh yeah, and Pacman Jones was Boba Fett. Good stuff.