White to play. Carlsen–Vachier-Lagrave, Opera Euro Rapid 2020. Carlsen played 31 Bd4+ Rxd4 32 cxd4 Bxd4 which should be drawn, though he won in the end. Can you find the much s-tronger move which he missed? Answers to be emailed to chess@spectator.co.uk by Monday 22 February. There is a prize of £20 for the first correct answer out of a hat.