Bxh7+ followed by Ng5+ and Qh5 is the classic attack on a castled king. It works only when the defenders can't cover h7 and g5 in time.
Key principles
- Typical conditions: bishop on d3, knight that can reach g5, queen that can reach h5, no black knight on f6
- Check whether Black can cover g5 (a bishop on e7) or h5
- Calculate the king's three retreats after Ng5+: g8, g6 and h6
Common mistakes
- Sacrificing when ...Bxg5 or ...Nf6 defends
- Not calculating ...Kg6