Multiply the possibilities with the Young Color Excel Energizers.
For each shade, 3 possible results:

Energizers

Ultra soft activator 6 vol (1.8%)
for soft and natural tones
*does not lighten
*does not cover grey hair

Soft 10 vol (3%)
for a discreet but visible change
*lightens between ¾ and 1 level
*aesthetic coverage

Plus 15 vol (4.5%)
for a better expression of the tones
*lightens between 1 and 1 ½ levels
*optimum coverage