The phrase "heat gauge" refers to a device or indicator that measures the level or intensity of heat. It helps us understand how hot something is or how much heat is being generated. Full definition
Sure, you'll earn experience and purchase upgrades, which include some new combos and situation - specific heat gauge attacks, but they don't alter the basic encounters. (rotorob.com)
The shield mentioned earlier adds a nice layer of depth (giving the player invulnerability for a fleet moment) and a gun heat gauge stops mindless blasting. (gamecritics.com)