This is a response to a r/Unity3d post that talked about many issues. The main issue I saw was how to separate responsibilities in your components. The example below is not *exactly* what I would do but it get's the point across.

AttackAbility.cs

public class AttackAbility : MonoBehaviour
{
  // this is how you declare a delgate (in case you didn't know)
  public delegate void OnDidAttackDelegate(GameObject target, AttackAbility attackAbility);
  
  // this the event that other scripts will subscribe on to know when we have attacked
  public event OnDidAttackDelegate OnDidAttack;
  
  private void Update()
  {
    var target = GetTargetGameObject(); // Pretend this function gets you your target
    if (ShouldAttack(target)) // pretend this function says it's ok to attack
    {
      Attack(target);
    }
  }
  
  private void Attack(GameObject target)
  {
    DealDamageToTarget(target) // pretend this function deals the damage
    
    // !IMPORTANT PART: Tell any subscribers that we just attacked
    if (OnDidAttack != null) // make sure someone has subscribed to the event
    {
      OnDidAttack(target, this);
    }
  }
}

GoldStealAbility.cs

public class GoldStealAbility : MonoBehaviour
{
  private AttackAbility _cachedAttackAbility;
  
  // we need to find the attack ability when we start up
  public void Start()
  {
    // get the attack ability on this gameObject
    _cachedAttackAbility = gameObject.GetComponent<AttackAbility>();
    
    if (_cachedAttackAbility != null)
    {
      // subscribe to the attack event
      _cachedAttackAbility.OnDidAttack += HandleOnDidAttack;
    }
  }
  
  // this is the method that is triggered on attack
  public void HandleOnDidAttack(GameObject target, AttackAbility attackAbility)
  {
    StealMoney(target);
  }
  
  public void StealMoney(GameObject victim)
  {
    // Put your steal money code here
  }
}