Misere Hackenbush is NP-Hard
  Hackenbush is a two player game, played on a graph with coloured edges where players take it in turns to remove edges of their own colour. It has been shown that under normal play rules Red-Blue Hackenbush (all edges are coloured either red or blue) is NP-hard. We will show that Red-Blue Hackenbush is in P, but that Red-Blue-Green Hackenbush is NP-Hard, when played under mis\`ere rules. 
Fraser Stewart
math.CO