Diag.1 is one of the Yagura Joseki called Katou Style (9-Dan Katou plays this strategy frequently.) It is the
After △N-33, it proceeds with ▲Nx+ △G32-33x (△Sx and △G43-33x are also available) ▲S-46 (Diag.2). △G32-33x means preparation for the attack from above. It doesn't look like a good shape, though.
In Diag.2, △N*86 is the
After ▲Px △Px (Diag.3), it looks like there is no piece to drop
To remove the threat of △Bx46,
In reply to ▲P-55, the attack with △N-85 ▲Sx86 △Nx97+ ▲Kx △P*85 (Diag.4) is effective. The silver on 86 cannot move due to the bishop's line. If ▲Lx is played instead of ▲Kx,
▲N*79 is the same as ▲P-55.
Therefore, ▲Sx is a common move in Diag.3. After that, it proceeds with △Bx ▲Bx △Rx ▲P*87 △R-82 ▲P-35 (Diag.5). Many pro players regard Diag.5 as slightly better for
In this way, even if the position is still in the middle game, the tactic like △N*86 would go well depending on the situation.