Nice! :D
Really good job, it sounds as alien-ish as alien-ish can get XD.
There weren't many melodies, but what there are right now are OK, and sound quite unique. The instruments were fine, apart from Eurogate, which completely ruined the creepy feel of the song. You shouldn't really use presets, or even instruments that sound like them :P. The effects were obviously the main part of the song, and were extremely well done. The bass was fine, and sounds quite alien-ish.
The transitions were fine, and the song flowed very well without sounding strange or anything. The structure was OK, and it built up from very calm to a little more action-packed really well without getting repetitive. I loved the intro, it was great, but the ending still felt like it needed to continue. I think you should remove the last note entirely, and instead start some sort of reverse-cymbal effect going into a loud reverbed kick. An alarm starts sounding right after, which slowly fades away, and while its fading, there's an action packed drum beat in the background, and some alien-ish instrument playing a loud, fast melody, while doing some alien sound effects in the background; maybe some sci-fi explosions and laser-shots. I think it would indicate that the aliens suddenly start attacking, since the song as it is now just feels like the aliens are found, and are walking around looking harmless. In short, I think you should try and continue this. Yikes, long paragraph. D:
The drums did the job really well in this song. They didn't sound too action-packed or too simple, but fit awesomely with the alien feel of the song. Nice samples too.
In all, it sounds really awesome and unique. Just take away that Eurogate and instead use a different instrument, and then I'd have nothing to complain about. You really should continue it :D.
9/10
5/5
-Review Request Club-