Energy system

Energy systems control the progress of players within a game by limiting the amount of time that can be spent playing, capping the number of rounds a player can initiate, or disallowing players from continuing the game without lives. Energy generally refills over time, influencing the frequency with which players can re-engage with the game. Energy systems frequently double as a monetization strategy - some games allow players to purchase energy as an alternative to waiting. These systems are frequently employed in free-to-play mobile games, where alternative means of monetization are necessary for development costs and players are expected to have frequent access to the games.

Not to be confused with the concept of expendable "energy" or "stamina" as a resource tied to specific in-game actions, such as the stamina wheel in The Legend of Zelda: Breath of the Wild [ゼルダの伝説 ブレス オブ ザ ワイルド] (2017) or the hunger meter in Minecraft (2011).