Organic Color Systems Intensifiers are designed to give deeper, brighter, more intense colors. Green intensifiers are ideal as an anti-red. Also add green intensifiers into 1 to 10 or all AH colors to increase green tones and give the hair a flat ash tone. Intensifiers can be used on their own when applied to pre-lightened hair as a semi-permanent color. They can also be added to conditioners and treatments as a temporary color. The lighter you lift the hair, the brighter the result and the edgier the color.