How to I subtly tint/darken my hair with manic panic dye?

I have natural light brown hair at the moment. A few years ago I used the black Raven dye, and it faded to a terrible pukey green within a couple weeks. I want a red tint, but not TOO red. more of a dark brown. What would I mix to achieve this? I was thinking maybe a few drops of black in the vampire red, and either leave it on for less time or add some water. I can't have "intense" looking hair due to work but I'm so incredibly bored with my current hair. I feel washed out and ugly and need some sort of change. I have to use manic panic because I'm very allergic to regular hair dyes.