Chess Tactics 3: The Discovered Attack

"Chess Tactics from Scratch: Understanding Chess Tactics 2nd edition" by Martin Weteschnik:

"The discovered attack has a strong schematic resemblance to the pin. As in the pin there are three pieces in a row. But in contrast to the pin there is a fourth point. The first piece and he discoverer are pieces of the same side; the third point or square of the other side. The fourth point is taken or occupied by the discoverer."

"A discovered attack is a simultaneous attack against two points where one attack against the first enemy piece is discovered by the attack on the second." 

"Chess Tactics for the Tournament Player" by Lev Alburt & Sam Palatnik:

"A discovered attack involves three pieces which are positioned on the same line (rank, diagonal or file). If the obstructing piece can move with a powerful threat (such as a check) then the piece it uncovers is free to capture an enemy piece."

"303 Tricky Chess Tactics" by Fred Wilson & Bruce Alberston:

"The discovery, another three piece lineup, illustrates the idea of a masked attack. A piece moving off an open line, unmasks an attack by a piece stationed in the rear. The attack by the stationary piece has to be dealt with immediately; this is particularly true if it is a discovered check to the King. But meanwhile, the moving piece is free to roam and inflict maximum damage."

Wikipedia:

"In chess, a discovered attack is an 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 threat 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 tempt. If the discovered attack is a check, it is called discovered check."


Here is an example in the Advance Variation of the French Defense, as shown by Wikipedia:

1. e4 e6
2. d4 d5
3. e5 c5
4. c3 cxd4
5. cxd4 Qb6
6. Bd3 Qxd4??
 

7. Bb5+ Winning the queen.

Ghitescu - Fischer, Leipzig 1960



1. dxc5?? Bxh2+!
0-1

Fischer - Spassky, World Championship 1972



1 ... Nd7?
2. Nd5! Qxd2
3. Nxe7+ Kf8
4. Rxd2 Kxe7
5. Rxc4

"Chess Tactics for the Tournament Player" explains "And White won a pawn and now has an extra exchange, which was sufficient to win."

Weteschnik's book does a good job of further explaining the elements of a discovered attack. He uses this position as an example:



The obvious move is 1. Bh7+ winning the queen. The discovered attack has four elements:

1. Principal attack (rook).
1. The principal attacker can never be a king, knight, or pawn. Only the queen, rook, and bishop can be the principal. 
2. Discoverer (bishop).
1. The discoverer can be any piece. "The discoverer need not only gain material at its target, but can also perform all kinds of tactical tricks from there afterwards." (Weteschnik). 
3. Victim point (victim piece/victim square) (queen).
1. "Nothing is better than an attack against the king. Even if your opponent gained your whole queen's wing, if you could find a mate all his material advantages will not matter. The strongest pieces, if pinned against the king, lose all their power, and even a check by a feeble little pawn has to be answered." (Weteschnik). 
2. "It is a little more difficult with other pieces." (Weteschnik).
4. Discoverer's target (king/h7).
1. "The victim does not necessarily have to be a piece: quite often it is an important square. For example, a strategic point of a double attack, or a square you need to occupy in order to give mate." (Weteschnik). 

Keep those in mind, as you try to solve these puzzles:

Marshall - Kupchik, USA 1926
White to play


Katalymov - Muhin, USSR 1976
White to play
  

Spindler - Deilitz, Correspondence 1973
White to play


Sliwa - Tarnowski, Poland 1952
White to play


Thiamann - Felbecker, Correspondence 1968
Black to play (Remember: "The discovered attack may be used to defend a piece indirectly")