Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...f5/4. Nc3/4...fxe4/5. Nxe4/5...d5/6. Nxe5/6...dxe4/7. Nxc6/7...Qd5/8. c4/8...Qd6

9. Nxa7+ was first played in Gligoric-Heidenfeld 1960. It's not entirely clear how Black is going to punish White for simply grabbing a second pawn and holding on to it - on the contrary, White still has the threat of Qh5+ on the board, so it may be Black that gets the punishment.

9. Qh5+ was played against Günther Möhring, the originator of the 7...Qd5 variation, in two Hungarian tournaments in the 1980s. As is usually the case for loud forcing moves, it's actually a little more drawish than the alternative. Black will probably come out of the looming queen trade with castling rights still intact, which isn't the case in the 9. Nxa7+ line.