Find me a strong bitter cocktail with gin and vodka. Not necessarily to add, but I like tonic, white or rosé dry wine, citrus tastes. I don't like cream and eggs. Preferably dark in color.

Based on your preferences for a strong and bitter cocktail that includes both gin and vodka, the most suitable option would be the **Aylesbury Tonic**. This cocktail combines the smoothness of vodka with the slight sweetness of red vermouth and the effervescence of tonic water, aligning well with your taste for tonic and complex, bitter profiles.

With an alcohol content of 19.2%, it offers a significant kick yet remains balanced with the herbal and fruity notes from the red vermouth. The addition of tonic water gives it a refreshing touch while maintaining its robust character. The cocktail's final presentation, accentuated with a dark hue from the red vermouth, aligns well with your preference for a darker color.

For a refreshing twist, you could garnish it with a lemon or lime wedge, adding a zesty citrus element without compromising the cocktail's sophisticated bitter profile. The Aylesbury Tonic stands out as an excellent choice to meet your cocktail cravings.