Motivated by Danskin's theorem, gradient-based methods have been applied with empirical
success to solve minimax problems that involve non-convex outer minimization and non-
concave inner maximization. On the other hand, recent work has demonstrated that
Evolution Strategies (ES) algorithms are stochastic gradient approximators that seek robust
solutions. In this paper, we address black-box (gradient-free) minimax problems that have
long been tackled in a coevolutionary setup. To this end and guaranteed by Danskin's …