FriendlyTankNew.cs

using UnityEngine;

public class FriendlyTankNew : MonoBehaviour
{
    public float speed;
    public GameObject AI;

    // private Rigidbody rbody;
    // private GameObject enemy;

    private const float posThreshold = -37f;

    // void Start()
    // {
    //     rbody = GetComponent<Rigidbody>();
    //     enemy = GetComponent<GameObject>();
    // }

    void Update()
    {
        transform.localPosition += transform.forward * Time.deltaTime * speed;

        if (transform.localPosition.z < posThreshold)
        {
            //Destroy(gameObject);
        }
    }

    public void Hit()
    {
        Destroy(gameObject);
    }

    private void OnCollisionEnter(Collision collision)
    {
        if (collision.gameObject.name == "Tank")
        {
            Destroy(gameObject);
        }
    }
}