Interesthing
I always loved Halo games so I was tempted to test this, got a bit disappointed you had such a simple and short thing done but, like it was said below, it's promicing, aside the things everyone already said the only thing that bothered me is that when I found the grunt that shoots I was getting shot before he appear at all so in the real game it means you better make short corridors or else it'll be really hard to know when they'll come out, also got me thinking how you'll make the sniper if you actually make one, but either way it's a nice concept and, like I said, promicing, so I'll wait for more from you.
Keep it up.