Discovered attacks
In chess, a discovered attack is a direct attack revealed when one piece moves out of the way of another.
Discovered attacks can be extremely powerful, as the piece moved can make a threat independently of the piece it reveals.
Like many chess tactics, they succeed because the opponent is unable to meet two threats at once.
While typically the consequence of a discovered attack is the gain of material, they do not have to do this to be effective; the tactic can be used merely to gain a tempo.
If the discovered attack is a check, it is called a discovered check.
1. Bd2+
2. _____
3. _____
4. _____
Answers
Bd2+ (Example: moving the bishops allows the rook to give a check. Once the enemy king moves out of the way, the white rook can take the enemy queen).
Bb5+ (Once black addresses the check, the white queen can capture the enemy queen).
Nf5+ or Ng4+ (There are 2 solutions!)
Bxh7+ (the bishop sacrifices itself to take the pawn on h7; once the enemy king takes the bishop, the your queen can capture the enemy queen).
1. _____
2. _____
3. _____
4. _____
Answers
Bxh7+
Nf6+
Rg5+
d5+