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
b1a1
b1f1
b1e1
b1d1
b1c1
b1b6
b1b5
b1b4
b1b3
b1b2
g1h1
g1g2
g1f1
a2a4
a2a3
f2f3
h2h4
h2h3
c3c4
f4e2
f4e6
f4g2
f4g6
f4d3
f4d5
f4h3
f4h5

## Board State Fen
4r3/pp3p2/1n1p3k/3p3p/3P1N2/2P5/P1P2P1P/1R4K1 w - - 2 23
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
b1a1
b1f1
b1e1
b1d1
b1c1
b1b6
b1b5
b1b4
b1b3
b1b2
g1h1
g1g2
g1f1
a2a4
a2a3
f2f3
h2h4
h2h3
c3c4
f4e2
f4e6
f4g2
f4g6
f4d3
f4d5
f4h3
f4h5

## Board State Fen
4r3/pp3p2/1n1p3k/3p3p/3P1N2/2P5/P1P2P1P/1R4K1 w - - 2 23
assistant
b1b5