We prove that finding an epsilon-approximate Nash equilibrium is PPAD-complete for constant epsilon
and a particularly simple class of games: polymatrix, degree 3 graphical games, in which each player
has only two actions. As corollaries, we also prove similar inapproximability results for Bayesian Nash
equilibrium in a two-player incomplete information game with a constant number of actions, for market
equilibrium in a non-monotone market, for the generalized circuit problem defined in [Chen, Deng, Teng,
2009], and for approximate competitive equilibrium from equal incomes with indivisible goods.