Not bad!
This game is actually a whole heck of a lot closer to Stratego than it is to chess, but who am I to say anything? I really like the concept of this game, and to some extent, the execution as well (the music, in particular, is perfect). There's just one thing that bothers me. Well, two things, actually.
1) On a continuum of luck and skill, chess is a game of 100% skill. It's good to take a solid concept like that and throw in some luck, but I think you've thrown in far too much here. Think of luck in games as ketchup on a burger; it adds some flavor, but if you glob on too much, it just ruins the whole thing.
The fact that my King might appear on the second turn and the enemy might choose the square next to him and pull up a Ghost when there's nowhere for my King to run...well, that's really no fun. What's even worse is that if you lose your king and queen and your opponent still has his queen, you're completely screwed. There is no way to survive at that point. It might be a good idea to let ghosts take out the queen, just to keep things interesting in situations like that.
Other suggestions: you should consider leaving some spaces free of tombstones, setting in advance the number of units of each kind, and other things to make gameplay a little more predictable.
2) Every piece moves exactly one space. I'm sorry, but that's kind of dull. It turns every match into an elaborate game of rock paper scissors, essentially. Giving some pieces different types of movement would add another layer of tactics to things. To do this well, you might need to increase the size of the board. I'm sure you can figure it out.
Anyway, good work on the whole. I look forward to seeing if you can improve on this!