How can I transition from a UIViewController to a SKViewController in Xcode playgrounds?

Currently, I am able to transition from a UIViewController to another UIViewController.

I use the following command:

PlaygroundPage.current.liveView = SecondViewController()

but if I use the same command to transition to a UIViewController with a SKView as the default view, I get the following error:

Cannot cast UIView as! SKView

What are the steps to resolve this issue?

Example: To transition from a UIViewController to another one, I use this:

//: A UIKit based Playground for presenting user interface

import UIKit
import PlaygroundSupport
import AVFoundation

class MyViewController : UIViewController {
    override func loadView() {
        let view = UIView()
        view.backgroundColor = .white

        let label = UILabel()
        label.frame = CGRect(x: 150, y: 200, width: 200, height: 20)
        label.text = "Hello World!"
        label.textColor = .black

        view.addSubview(label)
        self.view = view
    }
}

public class IntroViewController: UIViewController {

    public let descriptionTextView: UITextView = {
        let textView = UITextView()
        textView.font = UIFont.boldSystemFont(ofSize: 18)
        textView.textColor = .black
        textView.translatesAutoresizingMaskIntoConstraints = false
        textView.textAlignment = .center
        textView.isEditable = false
        textView.isScrollEnabled = false
        textView.text = ""
        return textView
    }()

    public let bb: UIButton = {
        let textView = UIButton()
        textView.backgroundColor = .blue
        textView.setTitle("Accept the challenge", for: .normal)
        textView.translatesAutoresizingMaskIntoConstraints = false
        textView.addTarget(self, action: #selector(click), for: .touchUpInside)
        return textView
    }()

    @objc func click() {
        PlaygroundPage.current.liveView = MyViewController()
    }

    public override func viewDidLoad() {
        super.viewDidLoad()
        view.addSubview(descriptionTextView)
        descriptionTextView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
        descriptionTextView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
        descriptionTextView.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
        descriptionTextView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
        // Do any additional setup after loading the view.
        view.addSubview(bb)


        bb.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true

        bb.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
                bb.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
        //        descriptionTextView.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: 0).isActive = true
                bb.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    }


    public override func viewDidAppear(_ animated: Bool) {
        let str = "Cheesy MI Line!"

        for i in str {
            AudioServicesPlaySystemSound(1306)
            descriptionTextView.text! += "\(i)"
            RunLoop.current.run(until: Date()+0.12)
        }
    }
}
// Present the view controller in the Live View window
PlaygroundPage.current.liveView = IntroViewController()

And to transition from UIViewController (UIView) to another UIViewController (SKView):

class GameViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        if let view = self.view as! SKView? {
            let scene = GameScene(size: self.view.bounds.size)
                scene.scaleMode = .aspectFill

                view.presentScene(scene)

            view.ignoresSiblingOrder = true
            view.showsFPS = true
            view.showsNodeCount = true

        }
    }

    override var shouldAutorotate: Bool {
        return true
    }

    override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        if UIDevice.current.userInterfaceIdiom == .phone {
            return .allButUpsideDown
        } else {
            return .all
        }
    }

    override var prefersStatusBarHidden: Bool {
        return true
    }
}

public class IntroViewController: UIViewController {

    public let descriptionTextView: UITextView = {
        let textView = UITextView()
        textView.font = UIFont.boldSystemFont(ofSize: 18)
        textView.textColor = .black
        textView.translatesAutoresizingMaskIntoConstraints = false
        textView.textAlignment = .center
        textView.isEditable = false
        textView.isScrollEnabled = false
        textView.text = ""
        return textView
    }()

    public let bb: UIButton = {
        let textView = UIButton()
        textView.backgroundColor = .blue
        textView.setTitle("Accept the challenge", for: .normal)
        textView.translatesAutoresizingMaskIntoConstraints = false
        textView.addTarget(self, action: #selector(click), for: .touchUpInside)
        return textView
    }()

    @objc func click() {
        PlaygroundPage.current.liveView = GameViewController()
    }

    public override func viewDidLoad() {
        super.viewDidLoad()

        view.addSubview(descriptionTextView)
        descriptionTextView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
        descriptionTextView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
        descriptionTextView.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
        descriptionTextView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
        // Do any additional setup after loading the view.
        view.addSubview(bb)


        bb.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true

        bb.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
                bb.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
        //        descriptionTextView.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: 0).isActive = true
                bb.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    }

    public override func viewDidAppear(_ animated: Bool) {
        let str = "Test String!"

        for i in str {
            AudioServicesPlaySystemSound(1306)
            descriptionTextView.text! += "\(i)"
            RunLoop.current.run(until: Date()+0.12)
        }
    }
}
// Present the view controller in the Live View window
PlaygroundPage.current.liveView = IntroViewController()

And I get the following error:

Could not cast value of type 'UIView' (0x7fff897d42e0) to 'SKView' (0x7fff87e20a98).