Enemy.cs

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

public abstract class Enemy : MonoBehaviour
{

    [SerializeField] protected int health;
    [SerializeField] protected int gems;
    [SerializeField] protected int speed;
    [SerializeField] protected Transform pointA, pointB;

    public virtual void Attack() // virtual keywords allows child to write it;s own Attack code or use this
    {
        Debug.Log("base attack called by " + this.name);
    }

    public abstract void Update();

}