A combination is a series of moves that when played in the correct order result (hopefully!) in an advantage. You may have a combination lock for your bike. To open the lock you must spin the dial to not only line up the correct numbers, but you must also have the numbers in the exact order. In chess, you must calculate and logically sort through all the capture variations in the correct order to find the variation that gains the largest possible advantage.
White to move
White has two capture choices to analyze in this position: 1.Bxb4 and 1.Rxc8+. Both must be analyzed carefully.
Lets start with 1.Bxb4. Black then has the choice between 1. … Qxb4+ and 1. … Rxc1+. If either one is good for Black, then 1.Bxb4 doesn’t work for White. Remember that you must assume that your opponent makes the best move.
At first glance, 1…Qxb4+ looks good for Black since 2.Qd2 fails to 2. … Rxc1+ because the White queen is pinned to the king. If White tries 2.Kd1 to protect the rook, Black can play 2…Rxc1+ 3.Kxc1 Qxf4+ and 4. … Qxe5. If White plays 2.Rc3, Black has several good choices like 2. … 0-0 with a huge lead in development and lots of threats.
1. … Rxc1+ also works for Black since 2.Kd2 fails to 2. … Qxb4+ 3.Kxc1 Qxf4+, as above. It turns out that both these possibilities after 1.Bxb4 work out well for Black!
Now checking out 1.Rxc8+, we see that it leads to a winning position for White. Black would have to play 1. … Bxc8 to recapture the rook. White could then play 2.Qb5+ as Black loses a bishop with either 2. … Qxb5 3.Bxb5+ with the threat of Bxb4 or if Black moves the king or plays 2. … Bd7 3.Qxa5 Bxa5 and 4.Bxa5.
David Twerskoi (1629)
Black to move
Zander Meitus (1309)
This position is from the 2008 Colorado State Scholastic Champion- ships. Can you find the four move combination that wins for Black?
Picking up tactical clues in this position, White’s rook on c2 is attacked once, defended once. The White knight on b5 is attacked once, protected once, and has only one retreat square: c3. White’s other knight on d2 is attacked once, protected twice. Notice that the Black queen has mating opportunities by invading on h2, should she get to d6 or c7. Knowing these important clues, can you now find the series of moves that wins the game for Black?
Black played the nice move 22. … Rxc2! which forces 23.Rxc2 recapturing the rook. Black then played 23. … Nxd2! forcing White to recapture the knight. Remember that the queen must defend the knight on b5. Therefore, White recaptured with 24.Rxd2 Black now attacks the knight with 24. … a6! Remember the knight has only one retreat square—25.Nc3. Everything is now set up for the fork 25. … Qc7! attacking the knight on c3 and mate with 26. … Qxh2+ 27.Kf1 Qh1 mate. White must avoid mate and played 26.g3 so Black took the knight with 26. … Qxc3 and went on to win the game. What a nice combination!
Note that changing the move order doesn’t work for Black—22. … Nxd2 23.Rxc8! Rxc8 24.Rxc8+ Qxc8 25.Qxd2 a6 26.Nc3 Qc7 as the White queen defends the knight on c3 and the only threat is 27. … Qxh2+.
If you take the extra time to calculate all the possible move orders and pick up the important clues, you will unlock the secrets in the position and find some pretty variations that lead to victory!
Todd Bardwick is the author of Teaching Chess in the 21st Century and Chess Workbook for Children. He can be reached at www.ColoradoMasterChess.com