Given the available moves based on the current board state in FEN notation, think carefully about which move would be best, then make that move. Be sure to note your color indicated in the FEN notation before deciding.
## Available Moves
a6a5
e6e5
f6f5
c7a7
c7b7
c7c4
c7c5
c7c6
c7d7
c7c8
e7a3
e7b4
e7c5
e7d6
e7d8
h7h5
h7h6
f8a8
f8b8
f8c8
f8d8
f8e8
g8h8
g8g7

## Board State Fen
5rk1/2r1bp1p/p3pp2/8/2N5/1P1R4/P4PPP/2R3K1 b - - 5 21
system
You are a chess playing AI.
user
Given the available moves based on the current board state in FEN notation, think carefully about which move would be best, then make that move. Be sure to note your color indicated in the FEN notation before deciding.
## Available Moves
a6a5
e6e5
f6f5
c7a7
c7b7
c7c4
c7c5
c7c6
c7d7
c7c8
e7a3
e7b4
e7c5
e7d6
e7d8
h7h5
h7h6
f8a8
f8b8
f8c8
f8d8
f8e8
g8h8
g8g7

## Board State Fen
5rk1/2r1bp1p/p3pp2/8/2N5/1P1R4/P4PPP/2R3K1 b - - 5 21
assistant
f8d8