Which are two most dark and sarcastic sign?

Before I even read this whole thing, I was thinking Capricorn and Scorpio. I like your analogy to illness, however a "dark" person isn't a bad person. Capricorns and Scorpios are cynical and in someways more brutally realistic than other people. I know many very positive Scorpios and Capricorns who love color and beauty so I disagree on that part, but for the most part I agree with you. Leos can be dark to but its more for the sake of being dramatic and having fun than actually believing the world is doomed. Pisces can be pretty dark if they've had a lot of problems and bad luck throughout their lives because they are very impressionable and dependent on their environment. But yes, I do agree with you.