Which invasions did I need to respond to? Help me figure out how this happened! What should I have done?

Yeah, I was fixing that as you replied!

Well, the first thing to look at are basic opening principles. I won't go into too much detail or find a link to you, because people always say something like "I know that already" - but the tl;dr version is that when you have a wall facing out, that's worth maybe 2 or 3 points per stone. If your opponent gets 3rd line territory and you get a 4th line wall, then your wall is probably worth at least as much as their territory. If we're talking 4th line territory and 5th line wall wall, probably the territory is worth more. Look at the board around move 42: you've given away 5th line territory to get a sixth line wall. You're going to have to use that wall very skillfully just to come out even.

In other words, you can't just have huge influence and when - your influence needs to be worth more than the cash you give away in exchange for the influence.

Past that, killing invasions is hard. If you want to get better at it, play more games, do more tsumego. You need to decide when to seal in invasions and when to control them based on your own reading of the life-and-death situation, and your estimation of how many points you need to win.

Thanks for looking at this!



No, please do go into more detail and find a link, if you're willing!



Ok, but... look at the board around move 85. Doesn't that wall give me a huge chunk of the board on the lower right quadrant of the board? In this case, that whole right side of the board was open and undeveloped and I had stones in the lower right corner, so I had a ton of space in which to use that influence.

Seems to me that if I had dealt with the invasion better, I would have had a huge lead fairly effortlessly based on that wall; am I wrong?



I had thought tsumego only applied to a small local area (like carpenter's square / J and L group problems) whereas here we're dealing with half the board that's being invaded. How does one read that out when there are many different ways White could try to live in that space?

Here is a post I did on basic opening principles previously:

viewtopic.php?p=101488#p101488




At 85, if black gets every single point that he has surrounded in the lower right, that's worth almost exactly what white has along the left side, and the game will be decided by who gets more points in the upper right. Or, if you get the lion's share of the upper right, you can lose some of the lower right and still win. I'm not sure I would call that a "huge lead", but regardless: can your walls "give you a huge chunk of the board"? Sure! They can give you a claim over a huge chunk of the board, anyway. How strong that claim is depends on what you can kill. If you don't know whether you can kill or not, then chances are you're going to have to give up some of that claim, one way or another.

All I'm trying to say is that if you think your stones give you territory when in fact they only give you a claim, or a zone of control, your attitude towards invasions is going to be off-kilter. Invasions are fun. You should welcome invasions.


Well, hmm. First, tsumego are mostly about reading. Memorizing the status of the L+2 group isn't going to help you solve most L+2-themed problems, and solving those problems should teach you much more than the status of one particular corner. Second, as late as 141, the invasion could still die. In fact, it looks rather like the sort of tsumego you would find in a book. Third, even if you succeeded at killing the invasion (preventing it from making two eyes), there still would have been reduction aji of the w155 sort... and if you had replied the way you replied in the game, white would have still captured j2 and resurrected his group. (And then there is the last few moves... surely you see the relevance of tsumego to those exchanges?)

Is that helpful?

I'm posting from my phone so please excuse the brevity.

Tumego are useful for this kind of situation because they help you judge how much space is required to make a live group, and teach you the skills you need to accomplish immediate goals. You can't read out every possible invasion, but you can learn to see that there are lots of places where white would have enough room to live. You may not be able to read a fight to the end, but you can learn to recognise and create strong or weak positions.

I'm with splatted that you need to do tsumego.
You let you oponent live each time.

For the group on the bottom for example:

- N4 is a bad move because it gives a lot of (cut) moves to white. I read that O4 better.
- Also you need to atari the stone on the first line (L1) in order to remove eyes.

=> this makes white die so you get a big area.

These two things are easy little things that you will directly see once you do some tsumego.

I once read a korean children tsumego book which stated a simple thing:

Every move you want to play, at least read 3 moves ahead. If you do that and tsumego then you will find yourself a lot stronger soon.

Oh there is another way of course, if you just play a lot of games your reading will probably develop on its own. But I'd still go for tsumego.

Have fun!

Cheers,
Otenki

A few comments, starting at move 131.



Edit: Added variations.

Main focus: When you have the advantage, solid play can reduce your opponent's chances.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

This may seem like a silly comment, but it only gives you that chunk of the board if you're able to defend it. You made a few mistakes and gave white a few eyes for free. If you hadn't made mistakes, it at least looks to me as though that's all black territory - but even so, that doesn't mean it'll necessarily be easy to defend.

I second this comment. It is possible to claim the entire board or large parts of it, but be sure the opponent will find ways to contest your claims. If you can successfully defend these claims, those parts of the board are yours. Otherwise, they will belong to the opponent. Go is about sharing through fighting - as oxymoronic as that sounds.