At first, Wolf Ranch’s homes look like stylish, modern houses with a touch of Texas Hill Country charm. But a closer peek shows their big secret: they’re made by ICON’s Vulcan II, a huge 3D printer that builds them layer by layer using a special concrete mix called “Lavacrete.” The result is a collection of single-story homes ranging from 1,500 to 2,000 square feet, with three to four bedrooms and two to three bathrooms, priced between $450,000 and $600,000—competitive for the Austin metro area.