Place the frozen meatballs and marinara sauce in a large skillet over medium heat. Stir gently until the meatballs are heated through and coated in sauce, about 10 minutes.
Preheat the oven to 350 degrees. Split the slider rolls and place the bottoms on a baking sheet.
Add one or two meatballs to each roll bottom along with a spoonful of extra sauce.
Cut each mozzarella slice into quarters and lay one piece over the meatballs on each slider.
Place the tops on the rolls and bake for 5 to 7 minutes until the cheese melts.
Remove from the oven. Slice the black olives in half and press two halves onto the top of each slider to form eyes.