I was minding my own business in the Ancient Burial Grounds in Mooshu. When I walked into the "catacombs" with the evil samoorais in them, what I expect to be a Samoorai was a GOLEM! After a few seconds they were samoorais again
You missed the part about the downloading icon in the upper left of your screen. You entered the area before the assets could be downloaded for that area - what you saw were placeholders (golems) that appear while the real assets are downloaded.
