Slightly lacking...err...
The deal: This attempts to convey that it's a demo, but I feel that it's a bit more... stationary than that. Notice that the first hit you do always does 5 damage, the enemy does 9, and the enxt round it's usually 8 and 8? it seems that the only randomness is dirived in the last part, where yuo will do either 2X8 (or 16, I dunno which) or 8, and they will kill you at the end. It's always 3 rounds.
If the author were trying to make a real demo, then they should have added a timer system That way, it would look less rigged. Additionally, since a demo is usually a debug version, a hin on the enemy HP would be great. A sort of "console". I could get into a primitive AI, but that would be a waste o' your time.