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
f1a1
f1b1
f1c1
f1d1
f1e1
g1h2
g1h1
c2b1
c2d1
c2g6
c2f5
c2e4
c2d3
c2a2
c2b2
c2c1
d2c1
d2e1
d2h6
d2g5
d2f4
d2e3
e2e4
e2e3
g2e4
g2f3
g2h1
b3b4
c3b1
c3b5
c3d1
c3a2
c3e4
g3g4
h3h4
a4a1
a4a2
a4a3
a4h4
a4g4
a4f4
a4e4
a4d4
a4c4
a4b4
a4a6
a4a5

## Board State Fen
rr4k1/3nppbp/bq1p2p1/3P4/R7/1PN3PP/2QBPPB1/5RK1 w - - 3 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
f1a1
f1b1
f1c1
f1d1
f1e1
g1h2
g1h1
c2b1
c2d1
c2g6
c2f5
c2e4
c2d3
c2a2
c2b2
c2c1
d2c1
d2e1
d2h6
d2g5
d2f4
d2e3
e2e4
e2e3
g2e4
g2f3
g2h1
b3b4
c3b1
c3b5
c3d1
c3a2
c3e4
g3g4
h3h4
a4a1
a4a2
a4a3
a4h4
a4g4
a4f4
a4e4
a4d4
a4c4
a4b4
a4a6
a4a5

## Board State Fen
rr4k1/3nppbp/bq1p2p1/3P4/R7/1PN3PP/2QBPPB1/5RK1 w - - 3 21
assistant
b3b4