I decided for my Halloween deck to be Dogmatika and Noble Knights because they seemed the most religious archetypes (Although I did consider using Lightsworn as well).
Some of you might be thinking "Why did you pick these two archetypes because that isn't even what Halloween is about." Allow me to explain my reasoning. Halloween used to be called "All Hallows' Eve" and Christians used this to mourn about people in the afterlife, Ringing bells for the people in Purgatory, and wearing something like a mask so if someone in the afterlife wanted to kill your they couldn't figure out who you were.
When we go trick or treating now it was actually because most Christians refused to eat meat until November 3 so they would bake Soul Cakes to hand out to other people and poor children would go from house to house and get a Soul Cake in exchange for praying for someone in the afterlife.
The Jack O'Lantern was originally a turnip, they symbolized the souls of the dead, were originally called Soul Lights and people use it to guide lost souls back to their family while also using them to keep Demons away from their houses and family.
Some people left bowls of milk and a large meal on their loved one's grave or their stairs while other baked pastries were known as "Bones of the holy" to give to the lost ones.
People light tindle fires and all-night vigil bonfires as a way to pray for the dead.