Escaping the Leviathan's Lair

I threw this together pretty quickly and it's pretty short. I want to make it better, any suggestions? I'm going more for chase music, but I feel like this almost sounds like battle music. 

For me it might be a bit slow for a chase, though the chord choice and general intervals you use are definitely apt. C7(#9) is great for that kind of atmosphere. 
The synth near the end was a little iffy for me. Might have not matched as well.

The synth was one of the things I was worried about, I wasn't sure if it fit or not and what I should substitute it with. I'm also trying to make it a bit longer and build a more intense sense of dread.

Awesome! Sounds like Battle with Gilgamesh from FF series. It got a little repetitive towards the end and would have used some variety in instrumentation or perhaps dynamics. Good stuff