C# 9, covariant return types

using System;
using System.Collections.Generic;
using System.Linq;

namespace CovariantReturnType
{
    class SkillsBase {
        public int Salute { get; set; } = 10;
    }

    class Personaggio {

        SkillsBase sb = new SkillsBase();

        public virtual SkillsBase GetSkills()
        {
            return sb;
        }
    }

    class SkillsRPG : SkillsBase{
        public int SaluteExtra { get; set; } = 0;
    }

    class PersonaggioRPG : Personaggio {

        public SkillsRPG Skills  = new SkillsRPG();

        public override SkillsRPG GetSkills()
        {
            return Skills;
        }
    }

    internal class Program
    {
        static void Main(string[] args)
        {

            Personaggio p = new Personaggio();
            SkillsBase skills = p.GetSkills();

            PersonaggioRPG pRPG = new PersonaggioRPG();
            SkillsRPG skillsRPG = pRPG.GetSkills();



        }
    }
}