Rider Gauges

A Rider Gauge (ライダーゲージ) is an energy meter on the chest armor plating of a Kamen Rider. Its function is to act as a way for the user of a Gamer Driver to see how much damage they have taken. If the Gauge energy reaches its lowest point, an alarm klaxon will sound and the Gauge will flash. The Rider or Riders in question who are in this predicament must do one of three things:
 * 1) Abort their operation by deactivating the Gamer Driver and retreat to tend to their injuries or to form a new strategy for fighting the enemy.
 * 2) Find a Recover Energy Item to heal or a defense-type energy item to enhance them to evade or negate oncoming attacks.
 * 3) Continue fighting while dodging attacks and avoid getting hit to defeat the Bugster.

If the Rider takes too much heavy damage, the gauge will drop to zero and the Rider will die or as Asuna put it, the Driver powering the suit would go into "Game Over".

When Genm got a Game Over, he bypassed the Riger Gauge by using the data of his death with the Bugvisor to create the Dangerous Zombie Gashat. This makes him a "glitch" in how the Riders operate normally, as his Rider Gauge is damaged and has no health, yet he is immune to damage to some extent. This was part of Kuroto Dan's evil plan as he wanted to create the "ultimate game" where the "player" could not die, but chose to use it solely for himself.