Would be very difficult. First issue is that the code is written in C++ using libraries that aren't compatible with Android (Android typically uses Java or some kind of wrapper). Then there'd be the issue of the game not being optimized for very small screens (phones have very high resolution, yet very low physical sizes). Menus and such would likely be unreadable without some heavy changes.
Overall, it'd probably require re-inventing most of the game. Would be an interesting project if someone else wanted to just reuse the assets and create the engine from scratch. But it'd be very time consuming (MG is the product of years of development). A reinvention would probably want to scrap the existing engine code, anyway. It's mostly undocumented and doesn't follow modern programming practices (I think the rendering file was something like 10k lines). Using an existing 3D engine would save a lot of time as opposed to writing OpenGL code (which is ugly as sin).
Either way, it's a ton of work that doesn't have that much pay off (although I admit that the concept of MG seems a little more fitting in mobile, due to the short, independent games).
