its a cool POW, but its fair to ssimple to be a game, but, it keep me enterteined for a minute or 2.
Need progression and atack paterns. This is a concept, now make it a game.
For that you need what i said, progression. Be it levels or more atack paterns, etc.
Keep going, it can be something. But this is not evena fraction of the work. (and why hp 40 if decrease in 10s, make it 4 aand 1s)