Hmm...

This was a good piece. It sounded nice and had a few good things. There was also a few bad things.

First off, I didn't think that it captured the "essence" of a boss battle. It didn't really feel epic to me.

Also, it was very rudimentary, you could have shook things up a bit more.

Now, I liked the percussion for the most part. It was right on beat, and although it was basic, it fit well.

Another good thing was the use of a lead. But, now that you know the lead, you need to work a bit on your bass.

Can I ask what program you are using? Overall, it was good! Keep up the hard work!