#===================================================================
# Jens009's Critical Flash
# August 4, 2008
# Version 1.0
# Description: Screen Flash when attacker deals critical damage    
# Aliased used:
#   jens009_add_critical_flash make_attack_damage_value
# Compatibility:
#   All systems.
#=====================================================================
# Start Game_Battler_Edit
#====================================================================
class Game_Battler

alias jens009_add_critical_flash make_attack_damage_value
#===================================================================
# Start Method edit
#===================================================================
def make_attack_damage_value(attacker)
  # Call Original Method
    jens009_add_critical_flash(attacker)
  # Check Critical Flag
    if @critical == true
      # Screen Flash
      $game_troop.screen.start_flash(Color.new(255,255,255,160), 20)
    end # END CHECK
  end # END Method Edit
end # End Class Edit
끝
Introduction
Created upon request. Script is self explanatory. White flash when critical flag is on.

Features
Version 1.0:
White Flash on attacker's critical hit
Compatible with any system