Well, without more details about which science fiction piece this Jack Darby is from, it's difficult to provide a quote. There are numerous science fiction universes with a vast array of characters. Maybe it's from a less - known indie sci - fi story? Or perhaps a more mainstream one like a Transformers - related work where there might be a Jack Darby? We need more information to give an accurate quote.
I don't recall any specific Jack Darby quotes off - hand. There are so many characters in science fiction that it's hard to keep track of them all. Maybe search for the name along with the title of the science fiction work you think he's from.
The JoJo manga is mainly in black and white. Colored versions exist but are not the norm. Sometimes, colored illustrations are done for promotional purposes or by fans.
I think it's great. The characters are memorable, the plot is full of twists and turns, and the battles are epic. It's a manga that stands out from the crowd.