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
a1b1
c1h6
c1g5
c1f4
c1e3
c1d2
c1b1
c1e1
c1d1
c1c5
c1c4
c1c3
c1c2
f1d1
f1e1
g1h1
a2a4
a2a3
b2b4
b2b3
f2f4
f2f3
h2h4
h2h3
d3c5
d3e1
d3e5
d3b4
d3f4
g3e5
g3f4
g3h4
e4d2
e4d6
e4f6
e4c3
e4c5
e4g5

## Board State Fen
r2q1rk1/p5bp/3p3n/1npPp3/4N1p1/3N2B1/PP3PPP/R1Q2RK1 w - - 0 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
a1b1
c1h6
c1g5
c1f4
c1e3
c1d2
c1b1
c1e1
c1d1
c1c5
c1c4
c1c3
c1c2
f1d1
f1e1
g1h1
a2a4
a2a3
b2b4
b2b3
f2f4
f2f3
h2h4
h2h3
d3c5
d3e1
d3e5
d3b4
d3f4
g3e5
g3f4
g3h4
e4d2
e4d6
e4f6
e4c3
e4c5
e4g5

## Board State Fen
r2q1rk1/p5bp/3p3n/1npPp3/4N1p1/3N2B1/PP3PPP/R1Q2RK1 w - - 0 21
assistant
b2b3