I used cyber purple but it's much darker than I wanted so was going to try ultra violent with "one step lightening and colour"
I emailed the company and they said it shouldn't be used on already coloured hair and may turn my hair orange (it's medium brown naturally but I've been dying it years)
That seems insane to me, as surely you'd only ever be able to use it once (if you can't then use it on coloured hair?)
Anyone got any experience of it?