While a decent game, it sorely lacks VARIETY.
The level and enemy designs are great but rudimentary. there are 5 enemy types total and the repeat through all 30+ levels.
The background is simple and effective, but is, again, repeated through the entire game.
Each section (after the "boss fight" - for lack of a better term) should be different from the last or advance the VERY bare bones "story".
This ggame could have used a bit more work. Its actually quite fun and addictive, but it just feels flat and uninspired.
The game itself is simple and all of the mechanics work as advertised. It's nothing we haven't seen before, but we've seen much worse.
It feels, to me, like a stripped down version of a HF shooter. Nothing over the top. The pace id steady for the most part - perhaps a bit on the slow side. Avoiding enemy fire is quite easy even without strafing upgrades.
The upgrading is good but, again, lacks variety. A couple of more choices in weapons, etc would've been nice. The shotgun is a tad disappointing. It isn't a traditional shotgun, rather it is a slower yet more powerful version of the machine gun.
The difficulty curve shoots WAY up (out of nowhere) at level 29. I went from not being hit at all during the levels to suddenly being unable to finish the level - despite having fully upgraded weaponry etc.
I thought the game felt too easy from levels 1 - 28. but to have the difficulty jump THAT much between levels just illustrates the lack of care and attention given to the game itself.
With work and inspiration this could be rather popular.