Definitely not the first time, but it is nice.
The graphics of this game are amazing, and it has some originality to it. It gets unnecessarily complex at points though. Simplifying HUD and upgrade screens to bare essentials would be more appropriate.. I wasn't sure at first why I could only place two enemies down because there was no price for them in their description.
The game's main appeal is that you spawn enemies rather than defend which is simple enough (the flash game Age of War managed to allow players to do both simultaneously and I personally prefer that concept just for entertainment value)
The game was fun and looks really cool though so at this point it's just nit picky things that are preferable for players like myself.