A strange little side quest
World Z Defense has plenty of company in a long tradition of players chasing timing, patterns and better decisions. The word 'checkmate' is linked to the Persian expression 'shah mat', used when the king was trapped. The surprising part is how quickly the next milestone followed. Computer Space reached arcades in 1971 and became one of the earliest commercial electronic arcade games, even though its controls proved demanding for many players. That history is one reason familiar mechanics can still feel new when they are recombined well.
