Preheat your oven to 350°F (175°C).

In a skillet, combine the drained oysters and green onions over medium heat.

In a mixing bowl, whisk together the heavy cream, milk, Worcestershire sauce, garlic powder, and black pepper.

Gently fold the oyster mixture into the cream mixture.

In a separate bowl, mix the crushed saltines with melted butter.

Pour half of the oyster mixture into a greased 9x13 inch baking dish.

Sprinkle half of the cheddar cheese over the first layer, then add the remaining oyster mixture on top.

Finish with the rest of the cheese.

Top with the buttered saltines and bake for 30 minutes.

Let the casserole sit for a few minutes before serving.