Building Enemy Aggro with Vector3.MoveTowards in Unity

When building enemy AI in Unity, Vector3.MoveTowards is the standard tool for simple, straight-line "aggro" (chasing the player). It moves an object at a constant speed without overshooting its destination.

How It Works

Vector3.MoveTowards(Vector3 current, Vector3 target, float maxDistanceDelta)

• current: The enemy's starting position (transform.position).
• target: The destination (playerTarget.position).
• maxDistanceDelta: The maximum distance moved per frame. Set this to speed * Time.deltaTime for smooth, frame-rate-independent movement.

Every frame, Unity calculates the remaining distance. If it is smaller than your max distance delta, it snaps directly to the target, completely preventing manual math jitter.

The Basic Aggro Script

Attach this MonoBehaviour to your enemy GameObject. It updates the transform every frame and handles basic rotation:

using UnityEngine;

public class EnemyAggro : MonoBehaviour
{
    [SerializeField] private Transform playerTarget;
    [SerializeField] private float moveSpeed = 5f;

    void Update()
    {
        if (playerTarget == null) return;

        // Move toward the target at a constant speed
        transform.position = Vector3.MoveTowards(
            transform.position, 
            playerTarget.position, 
            moveSpeed * Time.deltaTime
        );

        // Rotate to face the player
        transform.LookAt(playerTarget);
    }
}

Tip: While this movement logic must live in a MonoBehaviour, professional projects often keep the AI "brain" (detection radius, cooldowns) in separate, plain C# utility classes to keep the hierarchy clean.

Limitations & Alternatives

MoveTowards is perfect for flying enemies or simple environments without obstacles. However, it ignores physics and cannot navigate around walls. Choose your movement method based on your level design: