Last week I told you I was going to do a session report of the new Games Workshop game The Horus Heresy: Betrayal At Calth. In the process of writing that session report – the first session report I’ve ever done as part of this column – I realised that I don’t really know how to write a session report. And now I’ve said “session report” about a million times. So today, before I lay my session report upon you next week, an analysis of the mysterious beast we call the board game session report. A million and two now.