Got this achievement with a Tactician Witch's Hat equipped. This is not the normal Witch's Hat. I know there are many questions about where to get these items but I'm not sure where I picked it up (Online or Exhibition) or what car I was using when I got it. The achievement popped at the end of an online game I was playing. When I checked in the garage it said I had 55 centers with the hat equipped so I don't know if I needed 55 or 50.