RELATED: The Sims 4: 15 Must-Have Mods For Better Gameplay And in spirit with that disappointment fueled nostalgia, this writer has compiled a list outlining some of the best mods for the third installment in the Sims series. Since the Sims 4 has been a bit of a let down to date, many players have been flocking back to previous installments. Mods are downloaded codes and items made for an established game which gives players the ability to perform actions previously unavailable to them within the game. Though many devoted Sims players argue over which installment in the series was the best, in terms of both gameplay and the expansion packs that came along with it, almost every player can agree that the game would not be complete without the addition of custom content and mods.