SKScene needs to be added to an SKView which is a subclass of UIView. When you create the view controller, you can either set the view property to be an SKView or add an SKView as a subview, then add your SKScene to that SKView via the presentScene: method on SKView. Here's an example on how you could achieve that:
import SpriteKit
class SomeViewController: UIViewController {
func viewDidLoad() {
super.viewDidLoad()
let sceneView = SKView(frame: view.frame)
let scene = SKScene()
// Do any other scene setup here
view.addSubview(sceneView)
sceneView.presentScene(scene)
}
}
Sorry if there are small syntactical errors. Didn't have a chance to test this and my memory of the SpriteKit API is hazy. Hope this helps!