From the campaign:
Orcs Orcs Orcs is a game for two to four players, ages 13 & up, that combines two excellent game mechanics that have not been paired before (deck building and tower defense) and has players casting spells, squashing orcs and rolling up the score in the Orc Squash Tournament. The theme and game come alive with the outstanding art and components that you have come to expect from Queen Games.
Why 13& up? One of the orcs is unhappy that he is part of the Orc Squash tournament and is making a gesture that may be offensive to some people.