Great game. I'm very impressed that a 9 year old made this. A few suggestions:
1. Take input on the page rather than through a prompt. Current implementation breaks immersion.
2. I'd like there to be some time pressure. This can be done either by the opponent making their attacks on a timer (rather than taking turns the way it's done now) or by putting an explicit countdown for how long you have to solve the arithmetic problem. Maybe you can find some other creative way to put time pressure on the player.
3. I'd like a visual indication of when an attack has been charged.
Some of these are already on his plan. We've talked about turning the game into a real-time game instead of a turn-based game, and he was excited about that direction.
re: (1) I know what you mean, but the prompt component is a great way leverage browser UI for input without affecting the rendered website, so it makes good sense in this case.
1. Take input on the page rather than through a prompt. Current implementation breaks immersion.
2. I'd like there to be some time pressure. This can be done either by the opponent making their attacks on a timer (rather than taking turns the way it's done now) or by putting an explicit countdown for how long you have to solve the arithmetic problem. Maybe you can find some other creative way to put time pressure on the player.
3. I'd like a visual indication of when an attack has been charged.
4. Music/sound would be awesome.