The first run through was kind of rough, but that's true for almost any game. My second time through, I had no problems. Since the ball is only ever chasing you, it makes it easy, because you can just strafe out of the way, but, since your goal was to just make an AI for chasing, I wouldn't say that it is a problem.

One problem that has been pointed out is how your projectiles block your view. I was thinking, for a somewhat easy fix (I'm not a programmer, so I don't actually know how easy this would be to program) perhaps increase the FOV, and make the projectiles come from the cube instead, since it is slightly lower than the camera. This would mean that the projectiles aren't in the player's face, and the increased FOV makes it feel less cramped.

All in all, I had fun. It's a little easy because of the simplicity of the AI, but a complicated AI wasn't the purpose of this build. (Sidenote: I've played on newgrounds for years, but I never made an account. I just made this one to respond here, in the hopes that my review could help.) You keep being you, and have a nice day!

That took some getting used to before I could kill the opponent. All the special effects when I fire made it difficult to see much at all, and very difficult to see where the enemy was going and whether or not I was hitting him. That makes it tough, and I suspect most players would want to be able to see what they're doing better and have the challenge come from the opponent being powerful instead of having their own shots obscure their view.

When I was playing, most of the battle took place outside of the buildings area and in an open field. So it ended up being just a matter of holding left or right to strafe around and avoid being hit, while I tried to keep the enemy in the crosshairs and fire short bursts so my shots didn't obscure my view. Then I tried playing again and staying within the buildings area to see if that made it more fun, but it started to seem unfair that the enemy could sneak up and tag me while I was having trouble finding him at all among the buildings, and it got practically impossible to follow the enemy when he started jumping around. Then I got hit and thrown in the air and landed on a rooftop with a small fence-like thing at the ledge with no way of getting off.

This is a very nice engine (idk how much of the engine you made yourself or how much came with the programming package you were using), but there's still a lot of work ahead to turn it into a really fun game.

By the time I got a feel for what was going on, I was already half dead. By the time I read the comments below to learn it was possible to move, the game was over. Very difficult to spot the ball, because after it hits you and you fly into the air: it soars into the air to chase you. Then it hits before being spotted again, or at least too late to be targeted. Managed to do 2 damage before I died out of 100. Rating is proportional, because games are to have fun, not frustration.

I like the fluidity of the interface and simplicity of handling. I think it'd help matters to have some sort of map in an upper corner, to get a sense of where you and your enemy are. I also found aiming to be difficult, and I'm not sure what my weapon is doing to my target.

Possibly some power ups, also level 3 is extremely hard (maybe it's just me).
You could also add something dynamic to the level, like a elevator going up and down or a large piston of some kind.
It would also be cool if you could leap from building to building.