|Flash Stopper's concept art in Mega Man 4|
Flash Stopper is Bright Man's signature Weapon from Mega Man 4. When activated, the user will set off a bright flash that will freeze time for a brief period, immobilizing everything except for the player and Bosses that are not weak to it. The player can still fire uncharged buster shots while Flash Stopper is in effect. Regardless of the character using the weapon, the buster shots will have the aspect and rules of Mega Man's uncharged shots, that is, three projectiles will appear at the same time.
While used, the player can harm shielded enemies with their buster shots, and this extends to bosses, even those immune to this weapon, which while still moving, their shielded moves will not protect them while the Flash Stopper is activated. Barring key doors, level objects that react when the player touches them will not work unless the player remains on them when the effect stops. If the player is no longer standing on such objects when the Flash Stopper's effect wears off, the objects will act as if the player has never landed on them. To destroy a Weapon Block marked with the Flash Stopper, the player has to shoot it with the buster shot.
If the player changes the equipped weapon or visits the menu, the effect will disappear.
Bosses set to be weak to the Flash Stopper will be stunned when the weapon is activated so the player can shoot them with the buster shots.
- The Flash Stopper and the Time Stopper are commonly confused with each other due to how the weapons are named with the "Flash" weapon not belonging to Flash Man.
- Although everything on screen is frozen, certain entities that trigger the player character to enter certain animations can still cause them to occur despite not applying any other effect.