Currently, there are this many remaining to get:
1 Ki-84
8 N1K2
4 Ki-61
They are all fine planes. I flew Ki-61's in two scenarios so far (Rabaul, where I shot down 4 B-24's, 3 B-25's, 3 P-38's, and 1 F4U; and one frame of The Pacific War, where I shot down two B-29's).
The axis plane set is very strong vs. the allied plane set (P-38's, P-47's, F4U's, B-24's).
