I just read some more (tis a bt long to read in one), I got to the part where Cobalt gets into the archeangel
Some of the sentences are very well written, however there are a few with a few grammar errors, make sure to check your work :-)
As for the story, I like it but it seems a little like your rushing, Cobalt escaped the whole structure in a sentence, I feel it would have been better if you'd drawn it out a bit or made it a little more suspenceful, maybe he could have seen some flood and be forced to fight the before the timer ran out.
Any way good luck with the contest. I will read the rest later ;-)