Sigma were joined by MC Justyce for their epic Manchester Monster Mash-Up set. This image appears in the gallery:#MonsterMashUp 2016: ALL The Photos From Last Halloween's BIGGEST Party 10. Sigma were joined by MC Justyce for their epic Manchester Monster Mash-Up set. (Pic: PA) 77 images See the full gallery: #MonsterMashUp 2016: ALL The Photos From Last Halloween's BIGGEST Party