Chess challenge #1: Mate in one This is the first of a series of challenges I'll be posting regularly. In this case it is just a simple mate in one. This is the position:
 [Title &quot;White to mate in one&quot;]
 [FEN &quot;1Bb3BN/R2Pk1pr/1Q5B/4q2R/2bN/4Q1BK/1p/1bq1R1rb w - - 0 1&quot;]

White plays and gives mate. It seems very easy but there are a lot of pieces in the board. I'll be increasing or reducing the level of the challenges based on the answers.
It seems that


   Qa3


is mate in one. It is indeed harder than it looks at first sight, because there are so many pins.