# Subscribing To A Brain
### Create An Instance Of A Brain
A brain is a scriptable object, so create an instance of that scriptable object in your project folder.
(Hint\* *there can be more than one instance of a brain in any given project* :smile:)
Right-click in the project folder, go to Create -> Indie -> Brain
Create an instance of the Brain scriptable object
This should create the brain with a System Message, Message History, and Context.
(Hint\* *Add a system message to give the brain character and guidelines of how to interact with the player* :brain:)
### Reference A Brain
```csharp
public Brain brain;
```
### Subscribe
Subscribe this script to the brain to be analyzed for tools.
```csharp
private void OnEnable()
{
brain?.RegisterScript(GetType(), this);
}
```
### Unsubscribe
Unsubscribe this script from the brain when the script no longer needs to be considered by the brain.
```csharp
private void OnDisable()
{
brain?.UnRegisterScript(GetType());
}
```
### Full Example Code
```csharp
using UnityEngine;
using Indie.Attributes;
public class MyGameController : MonoBehaviour
{
public Brain brain;
private void OnEnable()
{
brain?.RegisterScript(GetType(), this);
}
private void OnDisable()
{
brain?.UnRegisterScript(GetType());
}
[Tool("MovePlayer", "Move the player to a specified position.")]
[Parameter("position", "Position to move the player to.")]
public void MovePlayer(Vector3 position)
{
// Method implementation
}
// Other methods...
}
```
---
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