Bring a large pot of salted water to a boil. Cook pasta according to package instructions until al dente.
Drain pasta and rinse with cold water to stop the cooking process. Set aside to cool.
In a large mixing bowl, combine cooled pasta with diced cucumber, orange bell pepper, cherry tomatoes, and red onion.
In a small bowl, whisk together Italian dressing, olive oil, balsamic vinegar, Dijon mustard, oregano, minced garlic, salt, and pepper.
Pour the dressing over the pasta mixture and toss gently until evenly coated.
Add chopped basil and parsley. Toss again to distribute herbs.
For the “eyeballs,” top mozzarella balls with a slice of black olive. Press gently to secure.
Gently fold the mozzarella “eyeballs” into the pasta salad, reserving a few to place on top for presentation.
Chill the salad in the refrigerator for at least 1 hour before serving to allow flavors to meld.
Before serving, give the salad a gentle stir and arrange any extra “eyeballs” on top for maximum spooky effect.