The Battle of Tuiuti was the largest and bloodiest field battle of the entire War in Paraguay and the South American continent, as it involved more than 55 thousand men. It was fought on May 24, 1866, in a swampy, sandy and difficult to navigate region called Tuyutí, in southwestern Paraguay. Consider as one of the hypotheses to be tested in the game that both the Paraguayan attack had been better coordinated and the allied defense had been better oriented – even if the latter maintained its expectation for a next offensive. And then you will see which maneuver will prevail, both being instructed with the best and with maximum effort. You have, in an insert in these rules, the game pieces and the game board, but you will need to acquire a ten-sided die (d10) or adapt to use two six-sided dice (d6). Regarding scales: for time, each Turn corresponds to 60 minutes; for terrain, each hexagon or hex is up to 250 meters; the forces game pieces represent, respectively, infantry and cavalry brigades, those of artillery regiments.