Possible Clues:

• O, the North should be like this!
• Nothing
• Below the North, on should see 15 and 25 down
• O, that's what the North should come to
• O, should 5 down in the end get like this?
• There's not a thing the North should do
• O, that's what the North should do
• O, 15 across should make this
• O, this should have got beheaded
• Nothing the knight should follow