Definition - What does Play Mechanics mean?
Play mechanics are the rules that govern the gameplay within a video game. Play mechanics dictate what the actions the users can carry out within the game environment as well as how the game’s artificial intelligence (AI) can react to a user’s actions. Play mechanics differ greatly according to the genre of game being played.
Techopedia explains Play Mechanics
Play mechanics control everything from how high a character can jump in a fighting game to how many units you can field in a strategy game. Play mechanics are at the root of the user experience and thus are the first thing to be planned out once an initial game concept is created.
Even in a finished version of a game, the play mechanics can be tweaked to make a game more or less challenging (hard, normal and easy modes). By choosing one of these modes, the rules of the game are changed. For example, choosing hard in a fighting game may mean that your characters' attacks do less damage, whereas the AI-controlled opponents move faster and inflict more damage.