The pieces above are all tattooed with only black ink (and some white highlights.) This is my preferred method for colorless tattoos. I've included these examples because I'm frequently asked what I mean by "blackwork" and how it differs from smooth black and grey. I will occasionally use a grey wash (diluted black) in really light areas, depending on the design, if I think it will be the best in terms of aging.
Below are examples of blackwork combined with a pop of color. My instagram is filled with examples of my full color pieces, both neotraditional/illustrative and anime if you would like to see more examples of those!