Tactics – The Fork

Tactics - The Fork

We are going to continue looking at tactical devices you can use to gain an advantage.
Tactics are short term plans which often force the win of material or the creation of another weakness.

Today we are looking at the fork:

Fork

The fork - capable of murder on the chessboard!

Like in the potato-based debacle above, we see the fork is a deadly weapon!

In chess, we use the fork to explain a scenario where we attack two pieces simultaneously. An example is given below:

White saves his skin by throwing in this nasty knight check which 'forks' the king and rook.

Both pieces are attacked; yet by being in check black MUST move his king and surrender his rook: 1...Ke7 2. Nxf7 draw.

Three things you will learn today

  1. The fork is a tactic where the attacker hits two pieces simultaneously
  2. Knight forks are much harder to spot!
  3. Forks are much better if you can create your own!

Part 1 of 3 - Understanding a fork

Your Turn! White to play

This is a wonderful example of the power of the fork!

The knight wants to hit two things at once - the king and rook. We know the knight can attack up to 8 squares of the same colour so we look and find 1. Nh6+ Kg7 2. Nxf7 and we've got a draw!

The knight is the most lethal piece to bring about a fork, as it's a low value piece in itself but capable of attacking many squares.

Types of fork

Including the king, every chess piece can create a fork:

  • The Queen can do diagonal pins or straight attacks and so is a lethal forker!
  • The Rook can do straight forks - usually best attacking one rank and one file:
  • The Bishop can do diagonal forks
  • The Knight can do L-shaped forks - lots of them!
  • Even the humble pawn can manage its own pins!
  • After 1. c6+! Kxc6 2. Bf3+ skewers the king and the queen goes or 1...Qxc6 2. Ba4 is a delightful harmony of the bishop and knight!

Summary of part 1

  • A fork attacks two pieces at once and can be done with any chess unit.
  • The fork is a particularly strong tactic if one of the attacked pieces is a queen or king.
  • As chess only allows one move per go, unless the 'forking' piece can be captured, the defender is likely to have to exchange some material

Part 2 of 3 - Sneaky Knight forks

Without a doubt, the hardest forks to see are knight forks.
Knight forks are very difficult to always see. In the above position, 1. Nf5+! nets a queen whereas if the queen were on, say g8, 1. Nc2+ also nets a rook.

The knight, due to the unfortunate placement of the king, covers g7 to a3 here! Amazing stuff.

How to avoid knight forks

Many beginners often play a brilliant game only to lose in a time scramble (or through missing it) to a devious knight fork, which sadly costs them a queen or another major piece.

Whilst the knight checks are harder to spot, there are some key ideas which can help you be on your guard.

Middle Knight

From the middle of the board, I can go to 8 squares!

Knights love being in the middle of the board. Keeping it at the edge limits its scope. Also note how the knight suffers from only attacking one colour of square on each move.

If you have, say, a queen and king left, keep the king on the dark squares and the queen on light squares and no matter how many checks the knight throws at you, they will never fork both pieces!

Red Yellow Green

The full scope of the knight

In the diagram above, the knight has a beautiful symmetry of where it can get to. The key points to note are:
  • It can get to the L shaped distances in 1 move (green)
  • It can get two squares away (e.g. d4 to b4) in 2 moves (i.e. it can attack in 1 move d4-c6!)
  • It hates the squares immediately next to it - d3, c4, d5 and e4 where it takes 3 moves to get there.
Make your king as safe as possible:
This was taken from round 2 of the fictional Copenhagen championship of 1992 with Jensen - Vilfort.
  • If black was to play 1...Ke5?! or 1...Kd6?! then 2. Nxc4+ will net a rook and should hold the game.
  • 1...Kd4 looks very tempting but remember the colours! 2. Nc2+ wins the queen
  • Vilfort found the best move in the game with 1...Ke4 and after 2. Nxc4 Rxb4 converted the material advantage in a further 20 moves.

Summary of part 2

  • Knight forks are the trickiest to see.
  • Stay off the same coloured squares to avoid knight checks.
  • Knights hate a piece right next to them, it makes them uneasy!

Part 3 of 3 - Creating your own forks

Just like with the other tactics, it's much more fun and much more realistic to have to create your own forks over the board. The opponent is unlikely to just gift you them but we've all done it!

Try your hand at "creating" your own forks below - find the move each time which will force a fork:

The sneaky rook check forces the king to an unfavourable square where a follow-up knight check is deadly.
The pawn check is devastating. If 1. c6+ Kxc6 (or the knight drops) then 2. Rxh6+ wins the queen!
1. Qb6+ forks the king on h6 and rook on g1. 1. Qe3+ is also perfectly valid!

Summary

  • Forks can be done by any chess piece and attack two pieces at once, often obliging the defender to surrender material.
  • Knight checks are the hardest forks to prevent in practice, as the sneaky knight can cover a lot of squares.
  • They are much more fun if you can create your own!