As pig farmers in Happy Pigs, players compete to raise healthy pigs by using strategic combinations of “Actions” (Feed, Mate, Purchase, and Sell) and “Tools” (Vaccines, Nutritional Supplements and Birth Amulets) during each round. Both the frequency to take these “Actions” and the number of “Tools” a player can buy are restricted by the number of players deciding to take the same action in any given round. Also, sometimes there are unexpected events (such as Pig Shows and Sausage Fest) which gives players great opportunities to outperform their peers.

There are 4 rounds to each season, and any unvaccinated pigs die at each season change. The game finishes at the end of four seasons, when all pigs are sold off at different prices in accordance with their sizes. The player with the most profit at the end wins the game.