I am going to go with the same concept but tweak it a bit. Instead of getting data from the screen, I am going to get data from the audio coming out of the speakers! This can get interesting now. There are things of course like VU Meters, which basically display the measurement of volume from an audio device.
So what would happen is as you hear the monster coming closer to you, getting louder, lights would light up indicating how loud the audio is coming from and in which direction. If the monster if coming from the right, you will hear it coming from the right, and the lights on the right side will be lighting up.
The first way of implementing this that I can think of is to get the loudness of the sound coming from the left and the right. Then it would be "displayed" on an array of the LED chain.
For example, if there is a low volume noise on the left, then there will be a little light coming from the left. If there is a very loud sound coming from the left, like a gunshot, then the light coming from the left would be large, and nearly in the middle of the array. If a large sound comes from both sides, the entire array would be nearly completely lit up.
Next I will talk about the programming side of it.