The Halloween decorations are already in the game. You can buy them from the off-season Halloween vendor in Hooligan's Route for 50 candy corn for a recipe book. This is just normal candy corn so cheap to get. Some 500 for everything.
breakdancing with Catalyst hammer skill 3 is my favorite. Having also baloon equipped looks hilarious as you kick it. Mystical Weapons are dope as hell with their own animal spirit from each weapon.