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
b1a3
b1d2
d1a4
d1b3
d1c2
d1h5
d1g4
d1f3
d1e2
d1c1
d1e1
d1d3
d1d2
f1a6
f1b5
f1c4
f1d3
f1e2
g1h1
a2a4
a2a3
b2b4
b2b3
f2f4
f2f3
g2g4
g2g3
h2h4
h2h3
c3c4
e5d5
e5e1
e5e2
e5e3
e5e4
e5h5
e5g5
e5f5
e5e8
e5e7
e5e6

## Board State Fen
r1bq1rk1/pp3ppp/2pn4/3pR3/3P4/2P5/PP3PPP/RN1Q1BK1 w - - 1 15
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
b1a3
b1d2
d1a4
d1b3
d1c2
d1h5
d1g4
d1f3
d1e2
d1c1
d1e1
d1d3
d1d2
f1a6
f1b5
f1c4
f1d3
f1e2
g1h1
a2a4
a2a3
b2b4
b2b3
f2f4
f2f3
g2g4
g2g3
h2h4
h2h3
c3c4
e5d5
e5e1
e5e2
e5e3
e5e4
e5h5
e5g5
e5f5
e5e8
e5e7
e5e6

## Board State Fen
r1bq1rk1/pp3ppp/2pn4/3pR3/3P4/2P5/PP3PPP/RN1Q1BK1 w - - 1 15
assistant
f1d3