Unity Singleton implementation for GameController, based on Flappy Bird Tutorial.

GameController.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class GameController : MonoBehaviour
{
    public static GameController instance;

    // Singleton Initialization
    void Awake()
    {
        if (!GameController.instance)
        {
            GameController.instance = this;
        }
        else
        {
            Destroy(this.gameObject);
        }
    }

    // Start is called before the first frame update
    void Start()
    {

    }

    // Update is called once per frame
    void Update()
    {
        
    }
}