Don't think it is legal...
The king might have sat on f7 via a6-b7-c8-d8-e8-f7 but after going to f7 the knight has no way to get into e8. d6 is the only way which checks the king forcing it to capture the bishop.
I don't see any other way.
"No, it's not legal" is almost never the correct answer in a retro.
Don't think it is legal...
The king might have sat on f7 via a6-b7-c8-d8-e8-f7 but after going to f7 the knight has no way to get into e8. d6 is the only way which checks the king forcing it to capture the bishop.
I don't see any other way.