Wow I like this a lot. The XP and skill mechanic is really fun. Only thing I would say (and maybe this was intentional like camouflage or something), but the enemies' design didn't really stand out to me. I initially didn't even know that there were any, and that I needed to kill them at the beginning. But I really liked the huge wave of guardians at the last shell. Pretty intimidating xD. Overall, great stuff!