CON_
There are 13 CON_ files with _ taking the values B, C, D, E, F, G, H, I, O, P, R, S, and T.
Each is of length 0xC0. After 0x40 bytes (which I have yet to analyse), there is an 11 x 11 map as shown below.
The code to choose which combat map to use is in ULT4 at $6FD5. The combat map is loaded at $706D.