Quality of the special effects reflected on performer (1-6)

I believe the answer is:

x-factor

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'quality' is the definition.
(I have seen 'Special quality ' mean 'x factor' so perhaps 'quality' could also mean 'x factor')

I can't explain the remainder of the clue.

Can you help me to learn more?

(Another definition for x-factor that I've seen is " Special quality".)

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