i just beat the game *including the overlord mastermind things* and i must say it was quite enjoyable all the way through.
as for why i didnt give it a 5 star rating, i felt that the upgrade system could use some work, i couldnt tell if the 1% boosts were doing anything for the most part. as for firing speed, it seemed to max out rather quickly.
other than that the bosses were good, and the difficulty curve was fair.
i found the shield enemies annoying but of course that is the purpose of them. so good job on that. perhaps a few extra enemy types would make the game more interesting?
i compare most "upgrade space shooters" with enigmata, mostly due to the very in depth upgrade system, and achievements.
keep up the good work. you created a very enjoyable game.