Sunday, July 6, 2014

Flash Intuitive Quiet Moves

Finally had the time and inspiration to conjure this post up :) I am going to share with everyone something general in Othello midgame positions yet also particularly specific in various scenarios. 

Chapter Zero: The Big Idea

More often than not, players play in two ways. 

One, is a more offensive, objective-driven manner, creating their game or shape on the board, the way they see the game would pan out. Players with this style, would try to gain access to key positions for creating patterns which they know would give themselves an edge to keep them in their own comfort zone. A simple instance would be a player always trying to feed others unbalanced edges because they know unbalance edges are susceptible to wedges and attacks.  

The second way would be a more responsive solution whereby players just counter punch opponent moves as they see fit. This is a more active and responsive strategy and I see players like Ben Seeley from America (known as foompykatt on playok) and Lai Meng Joo (this guy keeps changing his nicks on playok so often, it is hard to keep track, but if you see a nick online with about 1900-2200 range rated with funny words or phrases with a "0" (Zero) replacing a letter "O" where it should be, then it is most likely him). As much as I am still a learner from great players like themselves, I would like to give players an insight on such a way to play. 

In the Basic Class, we had established that a quiet move is defined as a move that flips disc in generally one direction and is up against a continuous row or column of your opponents' discs. Applying that idea, it would not be hard to deduce that with every move your opponent makes, it could "open" up new moves or unpoison certain positions for you to play a possible quiet move. With this idea, I named this concept the Head and Tail Theory

Chapter One: The Heads and The Tails

In order to aid people's memory to this way of thinking, I named it the head and tail theory with each row, column or diagonals people flip on the board emulating black and white rows snaking across the board. 

A simple example would be the following:



If White makes a move to A5 for example, I would call the last move that White made being the "Head" while the entire row that white has created from A5 to G5 would be a continuous row to be targeted by the opponent. G5 would then be the "Tail" of this "White Snake" created. Usually every move in Othello means flipping a couple of discs in a certain direction. In this case, White has flipped three discs to the left direction in the 5th row. 

The Head and Tail theory comes in that for every action at the head, there would be a possible reaction at the tail end of the row created. (sorry if it sounds like Newton's Third Law).



In this case, the square at the end of this row created would then be H5 which according to the theory would be the targeted square to play. While the use of the Head and Tail theory to derive quiet moves in a quick intuitive manner is tempting, one must always remember that it applies both ways. So before one decides to make the move H5 here, you would have to check whether you are opening up any easy moves for your opponent as well. 




After Black plays H5 (being the Head), it forms a continuous diagonal of discs from E2 to H5 with E2 being the Tail. Since there is a square at the tail end of this "Black Snake", D1 would be the direct reply for White. Knowing this, giving your opponent an easy response almost immediately would not be wise. 

Thus, if we conclude that the direct reply to H5 is not favourable, we should analyse other quiet moves that have opened up due to White's A5 move as the action of "unpoison-ing" moves does not always act in the main direction that your opponent has flipped discs. 




From personal experience in playing 1-minute blitz games, when one is short of time, there is always a need to "pounce" on the first quiet move I see in order to prevent a loss due to time loss. The flashes on the above diagram depicts those quiet moves. 

However, in order to do this, it is important to have a quick eye to identify quiet moves, and this head and tail theory would be able to help you quickly locate at least one of those moves. But most of the time, in OTB (on-the-board) games, one would have ample time and to efficiently identify such quiet moves would also be highly essential in order to make decisions.

One may ask, why is B3 a quiet move when it flips discs in two directions; both horizontally and diagonally. Reflecting on my incomplete and vague definition of quiet moves, I refer to the book written by Tetsuya Nakajima on his definition of quiet or good moves. Nakajima defines (if I interpreted his book correctly with my entry level of Japanese), that a quiet move or good move would be one that flips only discs that are surrounded by existing discs on the board as well as does not open up any new moves that are useful to the opponent. Playing B3 would flip a total of four discs in two different directions, of which, D3, C4, D5 are discs that would be surrounded by existing discs on the board, not opening up new moves to the opponent. While C3 which has also been flipped has only one adjacent square to B2 which poses minimal threat to Black if White were to play it.

I would say Nakajima's definition of quiet moves are even more precise. By observing the discs that you may flip with each prospective move, you would be able to tell in general if it was good. 

While of course there are many more things to consider in deciding if a move was ideal, a "Head and Tail" theory would give players a quick guide to locate at least one response that would not be all that bad. By observing which is the row or column that your opponent has just flipped, one would be able to identify what I like to call flash intuitive quiet moves almost immediately. 

Sunday, February 23, 2014

Advanced Class Initiated!


Advanced Class Initiated!


Hello everyone, it's been probably one year and nine months since I last came back to continue writing on this blog. During this past twenty one months, it's been a crazy time for me. I started off working at my first job, represented Singapore in the Othello World Cup 2013 in Tokyo, Japan at Tokyo Skytree complex, scored 5/7 wins at the 34th Meijin-Sen 2013 at Sumida Riverside hall at the Asakusa area to achieve a Japanese 3 Dan. Most recently, hosting the final Othello World Cup 2014 in Singapore at the Marina Bay Sands Convention Centre. 

After the dust of those events have settled, I have decided to come back to what I love doing, writing my blog to share my knowledge and experience in Othello with the world. I was surprised to see that the blog has had substantial page views over the past year and a half or so and I really appreciate all the support from visitors. Really hope that whatever I have shared has benefitted all of you one way or another in your Othello playing standards.

Remaining steadfast in our committment  to coaching Othello at local schools, this year, the Othello Organisation (Singapore) is also looking to kick start workshops free of charge for all people in Singapore (although targeting mainly students) to learn Othello. At the same time, I think for those who wish to learn from home, building online teaching bases or platforms would be great as well. Thus, I am also doing my part to build a teaching syllabus according to what I feel would be great ways for people to pick up this game. 

In the basic and intermediate class, essential terms and entry-level maneuvers in the game were covered. To complement the earlier items covered, the advanced class will be focused primarily from the opening to the midgame covering numerous standard sequences (as far as I can try to cover) for players to learn the possible plays as well as how and why particular sequences seems to, more often than not, show up in games between stronger players.

Friday, May 25, 2012

Intermediate Class Chapter Three

Edgeplay and Tempo

As mentioned in basic class chapter two, besides the theory of centralisation, there is also an equally important theory which is the one on edgeplay. Edgeplay is arguably one of the hardest part of the game. Deciding whether to give up and edge or keep an edge always puzzles many novice players seeking to climb to a higher level. Of course, in order to improve, one must clearly understand these related principles as much as possible.

Before we begin, we need to first define good and bad edges.

Diagram 3-0

In order to judge whether an edge is balanced or unbalanced, one would need to observe the discs on the edge based on the two center axes marked by the red double headed arrows shown in Diagram 3-0 above.

For example, the top edge would be an unbalanced edge for Black with 3 discs on the left of the vertical center axis and none on the right.

Another example, the bottom edge would be a balanced edge for Black with 3 discs on the left and right of the vertical center axis.

Furthermore, the left edge would be a prospective 4 disc balanced edge with 2 discs above and below the horizontal center axis.

Lastly, the right edge would be a 5 discs unbalanced edge for White with 3 discs on top of the horizontal center axis and 2 discs below the same axis.

In essence, to detemine whether an edge is balanced or not, one only needs to observe the discs on each side of both the horizontal or vertical axis. Like a weighing scale, if you have the same number of discs on each side, it would be balanced. If not, they are unbalanced edges.

Generally, balanced edges are better than unbalanced edges because unbalanced edges are susceptible to attacks such as the wedge and stoner techniques covered in the chapter before.

 

Defending an Edge

Starting from a very basic form of edgeplay would be about defending an edge.

Diagram 3-1
The first board on the left of Diagram 3-1 shows how White has just played D8 to approach to capturing the bottom edge. If Black takes E8, it would be a move that threatens to take control over the edge since it can approach to the prospective C8 next.

Thus, in order to defend the edge and retain control of the edge, White would have to follow up with F8 as shown in the center board of Diagram 3-1. The result is then shown in the third board on the right of Diagram 3-1 where White has control of the bottom edge marked by the blue double headed arrow. White is said to have defended its edge here.

 
Let us now take a look at what happens in the alternate scenario should White choose not to take F8 and defend its edge. This brings us to the concept of tempo.

Diagram 3-2
The first board on the left of Diagram 3-2 shows the result if White chooses not to take F8 to defend the edge, but rather selects playing C3 instead. This opens up an opportunity for Black to control the edge to C8 since White has given up the right to move by playing C3 instead of controlling the edge by F8. Also, the move to C3 by White opens up an easy centralising move for Black to F4. Thus, C3 should be clearly problematic for White.

After White decides not to play F8, but rather, to play C3, it is said to lose one tempo to the edge. Furthermore, when Black decides to take C8, White will have to make one more move to the exterior and "consume" more of its opponents' frontier or surface discs. This would result in White losing up to two moves worth of frontier discs which could prove as a costly mistake of not willing to grab edges.

Moving on to the center board of Diagram 3-2, there is a pressing need for White to change D6 into its colour because White would not want to give Black an easy move to F4 and also to prevent Black from forming a nice balanced edge to the bottom of 4 discs.

Finally, Black would follow by G8 in order to protect the edge below. Although this edge is momentarily unbalanced, Black can look to change the D6 disc into Black so that he or she can balance the edge by playing B8 in the future. This prospect is possible because C7 is a White disc.

Therefore, as general rule to safeguard tempo, when your opponent plays a move to the edge or approaches an edge you are controlling, there is a need to first consider taking the edge that he or she is feeding you. Should the edge be unfavourable to you (an attackable unbalanced edge), then you should avoid taking it and consider other options.

Wednesday, May 23, 2012

Intermediate Class Chapter Two

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.

Saturday, May 19, 2012

Intermediate Class 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.

Tuesday, May 15, 2012

Intermediate Class Commences!

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.

Tuesday, May 8, 2012

New Othello Platform on Yahoo Japan

On top of the much popular www.playok.com, there is a new Othello playing platform on Yahoo Japan!
The figure below shows the sample user interface.


The system runs on Flash and features an interesting checkered board as the playing board with the usual black and white discs. On top of that, there is a realistic flipping sound together with the disc flipping animation as you make each move.

Each user gets to select and even dress up their avatar in the game room. The best thing about this rating system is that you are ranked relative to the result of your first game as your first rating almost immediately. This removes the need for people to play say many games in order to climb up to a high rating immediately.

Overall, I am thinking this interface is really fun and there are a lot more active players at this site (usually 300-600) from time to time. Unfortunately, for those who do not really understand Japanese will need to learn a little bit of the language to make it convenient for you to register an account, and play games at the site of course.

Players who wish to play at the Yahoo Japan site can register an account here: http://yahoo-mbga.jp/stdgame/300004?_ref=aff%3Dyhm50004