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...Qg5/8. Qe2/8...Nf6/9. f4/9...Qxf4/10. Ne5

Black needs to defend against the check while keeping the knight on f6 to deny the White queen access to h5.

10...c6 is a sensible move that leaves two White pieces hanging.