Halloween season has been in full effect the last few days and Hollywood celebrities are going all out with their costumes. This year, musicians, actors, and models went out as all types of fictional and real life characters. Kylie Jenner dressed up as Christina Aguilera from her 2002 “Dirrty” music video and Tyga dressed up as Juelz Santana. Puff Daddy went as Thor and Lil Kim donned a bunny costume. Katy Perry transformed into Hillary Clinton and Swizz Beatz showed up as a mad scientist. Chief Keef also joined in the festivities and became BAPE, circa Lil Wayne. Check out the costumes below and let us know which one is your favorite.