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
a1c1
a1b1
d1a4
d1b3
d1c2
d1h5
d1g4
d1f3
d1e2
d1b1
d1c1
d1f1
d1e1
d1d7
d1d6
d1d5
d1d4
d1d3
d1d2
g1h1
a2a4
a2a3
f2b2
f2c2
f2d2
f2e2
f2f1
f2f3
h2h4
h2h3
c3c4
g3h4
f4g5
f4f5

## Board State Fen
r5k1/p2pqp2/b1p4p/6p1/4rP2/2P3B1/P4RPP/R2Q2K1 w - - 3 18
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
a1c1
a1b1
d1a4
d1b3
d1c2
d1h5
d1g4
d1f3
d1e2
d1b1
d1c1
d1f1
d1e1
d1d7
d1d6
d1d5
d1d4
d1d3
d1d2
g1h1
a2a4
a2a3
f2b2
f2c2
f2d2
f2e2
f2f1
f2f3
h2h4
h2h3
c3c4
g3h4
f4g5
f4f5

## Board State Fen
r5k1/p2pqp2/b1p4p/6p1/4rP2/2P3B1/P4RPP/R2Q2K1 w - - 3 18
assistant
f4g5