Preheat the grill for medium-high heat.

Mix chili powder, oregano, onion powder, cayenne pepper, garlic powder, salt, and pepper in a medium bowl; blend in softened butter. Spread butter mixture on each ear of corn, and place each one onto a piece of aluminum foil big enough to wrap like a burrito, twisting the ends to close.

Place wrapped corn on the preheated grill, and cook until tender when poked with a fork, about 20 to 30 minutes. Turn corn occasionally during cooking.