Awful storyline, difficult gameplay
This submission's saving grace is the concept itself and the animation. Since I spent so much time playing this, I felt obligated to leave a long review.
Like many reviewers have already stated, the gameplay is incredibly unbalanced. The earlier levels can easily be beaten without building anything but then it dramatically shifts somewhere in the middle levels to where it can only be beaten by camping on your ass behind multiple turrets until you have enough scrap to venture out. Once it seems like there's a basic strategy to just camp, collect scrap, and leave your base when you're ready the difficulty increases by another power of ten or so with the boss fight. It becomes impossible to stay stationary and you must constantly encircle the arena without stopping while spamming left click just to have a hope of surviving. If you even get near the hordes of enemies you're likely to die, because since there are so many firing so many things the game itself slows down, often creating a time delay with the directional controls that kills you in the process. Unlike a lot of other people here, I felt it was unfair to leave a review for this game until I had beaten the campaign in its entirety, which I did. It was very painful process since the final battle is nothing but running from enemies and hoping the rockets you're firing hit the boss to do a little bit of damage and not one of the robot drones which seem to have infinite amounts of health when you lose the advantage of building 34223423 turrets to keep them away from you. The weapon upgrades really do come in handy in the later levels (if you want to take the time to just leave the game running to collect scrap), but since the enemies become more powerful and increase in numbers it's impossible to hope to upgrade everything and live. Suggestions if you plan on doing bug fixes with this game (which I really hope you do) or on sequel creation would be fixing the balance issues and create a cap on how many enemies can appear on screen at a time, which would probably do wonders with the lag problems.
Typical "robots take over the world and there are few humans/one human left" story with multiple plot holes that just turns into asinine guy humor by the end. Perhaps introduce how/why things happened, and how he's able to create such incredible machines so quickly from scrap metal. Reminds me of a bad MacGyver episode where the engineer creates something from complete garbage and saves the day.
The game probably would have been so much better if you just said "to hell with the storyline" and just created a complex turret defense game. With the increasing difficulty curve it could be a very fun game were it not for the balance issues and lagging. The different types of turrets and upgrades are very impressive and fun to use in combination against the enemies, along with the upgrades for them. What bothered me about the turrets the most was that once they were placed, they were invincible. Build enough (like I said earlier) and you can just leave the game running while they rack up scrap for you. The gameplay would be much more interesting if everything could take damage, and perhaps also be repaired by excess scrap.
Not much to say here except that it was impressive. The cutscenes (although awful in terms of story) were well animated and had good transitions, and during gameplay I could notice all the details put into the backgrounds, robots, and the machines. The problem with the detail in the enemies was that it was another reason why gameplay could be so slowed at times. Too many turrets or enemies on screen and it became lag city. Other than that, kudos, I was impressed.
As much as I hate to do this, overall the game gets a zero out of ten. There were way too many problems that outweighed the few good things, and it would be much more playable and enjoyable if these were fixed or improved upon in future entries. I look forward to seeing more of your work.