Intermediate

Good Morning, Good Afternoon and Good Evening! Wherever you may be reading this from, I would first like to thank you for taking the time to continue reading the Othello strategies I have to offer you.

Chapter Zero: Five Steps to Winning in Othello
Well, if you have read through the Basic Class and have come this far to read on to this next Intermediate Class, I would assume that you are ready and intending to take your game to the next level.

It does not take much for one to understand the concepts introduced in the Basic Class. However, when both players understand the basic strategies, there is a need to probe further. In order to become a novice or intermediate player, you need to understand the basic process of winning an Othello game.

The standard process to Winning a Game usually involves the following 5 steps:

1) Apply Rule Number One, Two, and Three from the Basic Class and centralise or minimise to a point whereby your opponent has only left perhaps 1-3 free moves.

2) Grab an edge which can also be your anchor to prevent being wiped out (losing all discs).

3) Play moves to the edge that you have obtained (edgeplay).

4) Force your opponent to have only moves to the X-squares or side squares which will give you corners.

5) Grab the corner and extend the number of your stable discs by playing (or creeping) from the sides starting from moves from your corner.

Example:
Diagram 0
It is very common to see this sort of situation played out when Black as a more advanced player plays against a beginner playing White with both players refusing to move out of the center 16 square box. In this situation, Black has successfully performed Step One and minimised pretty well in the center and limiting the options that White has essentially to only 25% of the board as indicated by the arrows. In comparison, Black has a much higher mobility to more than double of White at 62.5% of the board based on the areas Black can play to.

With more options for Black and fewer options for White, it is apparent that Black has the upper hand. However, another very important factor to consider when reading the position is also which side has to play the next move.

If White has to play the next move when he or she already has such limited options, White would be at a great disadvantage for sure. However, if Black were to play next, then the situation would be completely different because Black's next move will create more moves for White and thus increase its mobility.

Diagram 0-A                                             Diagram 0-B                                              Diagram 0-C
As the game moves on, Diagram 0-A is a possible result when White continues to try to grab all edges at the start of the game while Black continues to centralise. In Diagram 0-A, it is White's turn to play and it is shown that White has essentially 5 possible moves and just 2 safe moves (not an X-square or C-square move)  marked by the green crosses.

Assuming White is really a player who likes to sweep and wrap around all the discs, B6 would be a logical choice for White. As a result, in Diagram 0-B, Black can then perform Step Two by grabbing an edge to prevent loss of all discs on the board to A6 which is also a quiet move.

After A6 by Black, it is reasonable to expect White to grab C1 as shown in Diagram 0-C with the entire row of Black discs since the usual beginner mindset is to grab the maximum possible discs at the start of the game.

Diagram 0-D                                               Diagram 0-E                                              Diagram 0-F
Diagram 0-D shows the end result after White has captured C1. Over here, what Black would really wish for is to be able to play a move to the A7 C-Square marked by the star which will result in White only having two choices to A5 or B7 marked by red crosses. Both these two moves will open two corners to A1 or A8 respectively for Black allowing Black to capture these two corners.

However, since Black has no disc along the E3 to C5 diagonal, the next step Black should do is to create an access for himself to A7 without creating many more moves for White. Diagram 0-E shows how black can easily play into H5 to cut for the disc C5 in order to access A7. At the same time, Black only releases one safe move for White to play at H6.

After White has played H6, Black can then take A7. The result is shown in Diagram 0-F which shows how White is now forced to play either A5 which will give up the A1 corner to Black or to play B7 which will give Black the corner A8. Over here, Black has successfully complete Step Three and Step Four altogether by playing edgeplay and forcing his or her opponent to give up the corners.

Diagram 0-G                                               Diagram 0-H                                            Diagram 0-I
Finally, in Diagram 0-G, Black is able to capture the corner A8 after White has played B7.

As mentioned in the Basic Class, corners are stable as well as all adjacent discs or diagonally layered discs from it. Thus, the consequent strategy for Black after it has obtained the corner A8 is to expand its influence using its strength which is the stable corner A8 in either the top direction or to the right of the board as shown in Diagram 0-H.

A typical ending result would be something like what is shown in Diagram 0-I when Black has successfully played out the edges from its corner performing Step Five. It is obvious that Black has no more worries from here on out in losing the game if Black continues to advance in the three main directions beginning from the edges.


With that, I end off Chapter Zero of the Intermediate Class on how we should go about winning a standard game. Out of the Five Steps to Winning in Othello, the easiest steps would certainly be Steps Two to Five.

The main step that really gives us all problems is Step One which involves running your opponent out of moves. The following chapters will continue to explain how to carry out Steps Two to Five correctly and effectively while the Advance Class will talk about the hardest step which is Step One.


Chapter One: Openings

While it is possible to apply Rule Number Two from the basic class of playing group, small, inside to most centralising openings, there is always a limit to what a general guideline can provide for you. Some openings focus more on the centralising theory while others requires in depth study of the edgeplay and checkerboarding techniques.

There are perhaps close to 100 types of standard openings each with their given names. The names of these openings and their starting few moves can be found at this website: http://www.samsoft.org.uk/reversi/. Although it is not advised for one to immediately start memorising all the openings provided there and their consequent sequences, it is always useful to have good knowledge of at least one or two openings for each colour so that you can develop your own signature opening.

In the Wzebra software, most openings are named after players who have played it first or have played very well in them. For instance, there is an opening called Tamenori which is named after the 7 time world champion, Hideshi Tamenori. However, these openings are mostly named after animals in Japan and they refer to certain openings to tiger, rabbit or snake variations. These are usually named based on the shape of the board.

We will first study the wipeout openings in order to avoid losing too early in the game and study the tougher openings later.

Wipeout Openings

There are also openings built to kill opponents who follow Rule Number Two too strictly without watching closely what would happen in at least one move ahead. These openings are called wipeout openings. The website that I have recommended above covers many possible wipeout variations. However, in real game situations, wipeout openings that can actually work to trick an opponent is far and few.

I will show here some wipeout openings I personally believe would be more likely for novice players to fall to. I will first give the entire sequence of the wipeout opening and explain the important moves accordingly step by step.

Rose (-8) Wipeout Trap

The sequence of the wipeout trap is: F5D6C5F4E7F6G5E6E3

Diagram 1-A
Following the first 4 moves of the sequence given above, Diagram 1-A shows the resultant shape. Over here, it is common for Black to play E3 in order to make a setup move to D3 or E6 to play small and group as well as to centralise his or her discs.

However, to set up the wipeout opening, one would need to play E7 which is evaluated to be (-8) by Wzebra. This sort of dispersive move will lure White to make the next move using the F5 disc.

Diagram 1-B
In this situation, it is possible that White would be considering either the G5 or F6 move. Since F6 forms a relatively more compact shape as compared to G5 which forms a more elongated shape, it is more likely that F6 will be selected over G5.

Diagram 1-C
After F6 is played, Diagram 1-C shows the final set up move that is required of Black to form a large frame by playing G5.

Diagram 1-D
Over here, after Black has played into G5, E6 becomes an obvious "hole" or gap to really jump into for playing small, group and inside following Rule Number Two that is widely known among all novice and above players. Thus, White as an unexperienced novice player may decide to move immediately into E6 without thinking much. The result is shown in the second diagram of 1-D.

As a result, Black would be able to play E3 and perform what is called a wipeout opening in order to sweep all of White's discs in one move, forming a nice Black Diamond shape in the center. Since both players are unable to play any more legal moves, both of them should pass and the game would end here.

By the rules of the game, if there are any empty squares at the end of the game, they would be awarded to the side which has more discs on the board. In this case, there are 13 black discs but no white discs. Therefore, Black would win by a score of 64-0 which is the largest margin one can win in an Othello game.

Lesson Learnt: The lesson to be learnt here is that before making your move, the minimum consideration for each move should be at least visualising 1 move ahead before you make your current move. In other words, when you plan to play a specific move, anticipate at least what your opponent might play in response to avoid moves that will immediately lose all your discs and get wiped out.

Intermediate Techniques: Wedge and Stoner Traps

In order to continue improving, it is highly essential for one to learn more advanced techniques such as the wedge and stoner traps.

The Wedge
Diagram 2-1
The following diagram shows a typical example of what would happen if you as a novice player with some techniques learnt, plays against one of your counterparts who is a maximiser (one who likes to grab edges and flip many discs at the start of the game). In this Diagram 2-1, we see that Black is left with no more "safe" options and is forced to play into either X-squares or C-squares which are dangerous since they would give your opponent corners.

However, is Black really sure to lose from here? Think again.

Diagram 2-2
From the first board of Diagram 2-2 on the left, the first we need to note is that White has two unbalanced edges. One on the bottom and one to the right of the board. These unbalanced edges are definitely weak points of White's game that Black could make use of.

On the second board, G8 would be one move that Black could play in order to perform what is called a sacrficial wedge. When G8 is played, the black disc on G8 threatens to take the A8 corner. Thus, White must defend it by taking the H8 corner. In this case, Black would have sacrificed the H8 corner to White.

However, after White has played the H8 corner, the shape shown in the third board on the right shows how H7 is an opening that Black could play and wedge in between the H8 corner and the unbalanced H column of discs that White already has on the board. If Black plays H7 here, it is interesting to note that White can no longer change or flip the H7 disc and that Black would be able to play and capture the H1 corner on its next move.


Black can be said to have sacrificed the H8 corner in order to wedge into H7 in exchange of the H1 corner. Also, in this case, once Black has capture H1 corner, it can also look to capture the A1 corner next. Essentially, it has sacrificed one corner for two corners which is definitely a great deal for Black.

This techinque is one of a more intermediate endgame technique that one could learn. It would prove very useful against players who like to grab edges.
The Stoner Trap
First played by John Stoner, the stoner trap is another technique one would need to be well versed in. Once executed correctly, the one who wields the stoner trap usually ends up winning the game due to the number of moves one could gain from playing it.
Diagram 2-3
Diagram 2-3 above shows a standard example of how a stoner trap can be executed by Black playing G7. In order to successfully execute a stoner trap, one must fulfil the main three conditions:
1) Momentary Diagonal Control
2) Access to the Attack
3) Poisoned Discs of your Opponent
Diagram 2-4
The first key here is to maintain this momentary diagonal control along C3 to G7 after the G7 move is made into the dangerous X-square shown here in Diagram 2-4 on the right.
This diagonal control move (with the whole diagonal being only the discs of your colour) sets up the stoner trap for Black because there is no way that White can immediately take the corner to H8 since it does not have any access to it at the moment.

Thus, G7 would be setting up the first condition of the three as the momentary diagonal control.


Diagram 2-5
After G7 is played, it is natural that White will try to capture C3 so it can target the H8 corner next. Thus, C2 or B3 may be played by White here. In this example, B3 is played.

The next move is the main attack move of the stoner trap which is F8 marked by a black cross here. Of course, the most important condition to meet here would be the access for Black to attack. The crucial disc here is F6 which gives Black access to F8 in order to launch the corner attack to A8.

To complete the stoner trap, this step is crucial to be executed successfully so the access to the attacking square at F8 is important.


Diagram 2-6
The first board on the left of Diagram 2-6 shows the shape after Black has attacked White with F8 move threatening to take the A8 corner. The natural response here for White would be to play G8 in order to flip the F8 black disc into white so that White can prevent Black from taking the A8 corner. However, by playing into G8 White will also flip the G7 disc because of the G5 and G6 poisoned discs. The result is shown in the second board on the right. If White chooses to play G8, Black would be able to take back the corner of H8 it originally offered to White by playing G7 and also at the same time get A8 corner next. Essentially, Black would be able to obtain both corners at the cost of nothing this way. Thus, White must not respond with G8 here.

The main reason why G8 could not be played is because of the third condition, which is having poisoned discs of your opponent along the vertical axis involved (in this case column G). In order to give White this "painful dilemma", you must make sure that these poisoned discs stand when executing the offense at F8.

Diagram 2-7
The first board on the left of Diagram 2-7 shows (after the discussion above) how White is left with no choice but to settle by playing the H8 corner. At least this way, White would be able to secure one stable disc which is H8 itself. The result is shown in the second board on the right.

Over here, Black will have to immediately follow by taking the A8 corner since White is already threatening to play G8 in order to secure the bottom edge. Thus, Black must take A8 now. This would be something similar to a wedge in a sense that there has been a one-for-one exchange in corners.



Although there has been an exchange in corners for both parties, what White has gained through the process is just the H8 corner which is the only stable disc it gained. On the other hand, Black has managed to gain not only the A8 corner, but also majority of the lower edge which consists of 6 stable discs!
Now which colour would you prefer? Most certainly, one who wants to win the game would prefer Black. Looking further ahead into the game, the 6 stable discs that Black has gained to the bottom left would act as a very useful anchor or leverage it could make use of in the later stages of the game to flip more discs at crucial positons.
I hope this example has clearly explained how a stoner trap may be executed correctly.

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