Monkey Game Development：Beginner's Guide

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Time for action — moving the enemy paddles

Computer-controlled movements, or the so-called Artificial Intelligence (AI) , are sometimes very hard to create. But for a start, we will keep it very simple. And simple will be the key here. Our computer-controlled movement will look like this. One paddle will move with a speed of 10 pixels up and down, the other with a speed of 5 pixels in the opposite direction.

For this, you need to create a new method, called ControlEnemies.
```
Method ControlEnemies:Int()
```
Next, we update the paddles' Y positions. As we have two paddles to control, we will use a FOR loop for this, so we don't have to repeat the code. Remember that arrays in Monkey are zero-based.
```
For Local ep:Int = 0 to 1
eY[ep] += edY[ep] 'Update the paddles Y position
```

Next, we will check if a paddle reaches the top wall.

If eY[ep] < 25.0 Then 'Check if paddles reaches top wall
eY[ep] = 25.0
edY[ep] *= -1 'Revers its Y speed
Endif

Now, we will check if a paddle reaches the bottom wall.

If eY[ep] > 455.0 Then 'Check if paddles reaches bottom wall
eY[ep] = 455.0
edY[ep] *= -1 'Revers its Y speed
Endif

Close the FOR loop and the method.
```
Next
Return True
End
```
To actually get the enemy paddles moving, we need to call our new method from within the UpdateGame method.
```
ControlPlayer()
ControlEnemies() 'Control the enemy
Return True
```
Again, and like always, it is a good time to save your changes. For further progress, you can load up the file Pongo_06.Monkey.

Cool! All paddles are moving. Now only the ball is missing. Let's get rollin'!