Wow, this is a very polished game! I find that one of the strongest elements of your entry is its unique atmosphere - it's very creepy (good choice of artistic theme and music!), yet also somehow to me nostalgic to the days where enemies were simple colors/shapes (Demon Attack?) and sounds were simpler waveforms (I especially love the enemy spawning sound!). The game, although very difficult, is also quite fun and I love the little particles splattering everywhere from the bullets. Very well done!