SettingsPersistance.cs

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

public class SettingsPersistance : MonoBehaviour
{
    public static SettingsPersistance INSTANCE;

	[HideInInspector] public Difficulty difficulty;
    [HideInInspector] public int turnDuration;
    [HideInInspector] public int maxPoints;

    void Awake()
    {
        if (INSTANCE == null)
        {
            DontDestroyOnLoad(gameObject);
            INSTANCE = this;
        }   

        if (INSTANCE != this)
        {
            Destroy(gameObject);
        }

		defaultValues();
    }

	private void defaultValues()
	{
		difficulty = new Easy();
		turnDuration = 8;
		maxPoints = 3;
	}
}

public abstract class Difficulty
{
	protected float costModifier;
	protected float speed;
	protected float jumpForce;
	protected float force;
	protected float maxStamina;
	protected float speedModifier;

	public float getCostModifier()
	{
		return costModifier;
	}
	public float getSpeed()
	{
		return speed;
	}
	public float getJumpForce()
	{
		return jumpForce;
	}
	public float getForce()
	{
		return force;
	}
	public float getMaxStamina()
	{
		return maxStamina;
	}
	public float getSpeedModifier()
	{
		return speedModifier;
	}
}

public class Easy : Difficulty
{
	public Easy()
	{
		costModifier = 1;
		speed = 4;
		jumpForce = 5;
		force = 0.8f;
		maxStamina = 20;
		speedModifier = 2;
	}
}

public class Normal : Difficulty
{
	public Normal()
	{
		costModifier = 2;
		speed = 3;
		jumpForce = 4;
		force = 0.8f;
		maxStamina = 15;
		speedModifier = 1.5f;
	}
}

public class Hard : Difficulty
{
	public Hard()
	{
		costModifier = 3;
		speed = 2;
		jumpForce = 3;
		force = 0.5f;
		maxStamina = 15;
		speedModifier = 1.2f;
	}
}