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Tip: It is much easier to play on mobile devices than PCs, for you can use more than one gooball at the same time on mobile devices.
When you open the game, you can see a planet (Or Earth?) on the left of the screen. Click the green hill. It's chapter 1.
contents: show
Well, you can see the tower base and a pipe in the sky, drag n' drop a gooball to create two lines and a gooball on the top.
Obsessive Completion Distinction Criteria: (Also known as OCD, it means the final chellenge in each level) Collect at least 11 balls or more. If you put as the picture shows, will finish it! After you got an OCD, this level will add a little flag. My record: 11.
Just build a small bridge to the other side, or you could build a tower and let it fall down. This way needs more experience.
Build like this:
OCD: Collect at least 16 balls or more. If you build the bridge like the picture shows, you will get it! My record: 16.
At the bottom of this level, you can see some white gooballs (They are called Albino gooballs) sleeping.
When they are sleeping, you can't use it to build. You have to use the gooballs which are waking to build near the sleeping gooballs.
After they wake up, they can be used to build to the top!
OCD: Collect at least 22 balls or more. I haven't finished it. Welcome any solutions to this chellenge! My record: 18.
Also, when you finish this level, World of Goo Corporation will be unlocked, all extra gooballs you collected will be sent there. You can use these gooballs to build a giant goo tower and compare with others!
From this level, you can see some insects flying on your screen (In some level they don't appear), they are very useful, when you get trouble, you can click one to go back by one move.
Don't let gooballs touch the wheel gear, it will damage the gooballs! Don't worry if the goo tower is too heavy. There is water at the bottom. And here is the solution:
OCD: Collect at leat 42 balls or more. Well, my record is 41. But still, suggestions are welcomed.
After you finish this level, there are two levels to choose to beat.
When you come to this level, you can see the gooballs are all in green (They are called Ivy gooballs, they can be replaced.)
If you use all the gooballs, you will not be able to reach the pipe. So you have to take apart some Ivy gooballs and place them again.
And after you reach the top, you can even remove some Ivy gooballs until 2 gooballs left:
OCD: Collect at leat 16 balls or more. If you collect all the gooballs and just 2 gooballs left, then remove a gooball quickly to the pipe. My record: 16. (You can't collect more than 16 balls in this level.)
This level is in a rotating machine. If your tower falls down, just remove some Ivy gooballs and rebuild your tower.
OCD: Collect at least 35 balls or more. Just like the previous level, leave two gooballs and send the other gooballs to the pipe and at last needs some speed.
(Also, you can't beat my record.)
In this level balance is the most important! First, use the Ivy gooballs to wake up the gooballs at the bottom.
And then use the Ivy gooballs to build to the pipe. You can remove until two Ivy gooballs left.
OCD: Collect at least 25 balls or more. My record: 25. (You can't beat me record, either.)
Let's go back to the other side.
In this level you can see some red gooballs. (They are balloon gooballs, they can give gooballs a force of upwards.)
Use the balloons to let the gate open and then remove some of the balloons to the gooball square to fiy to the pipe.
OCD: Finish his level in not more than 16 seconds. My record: 14 seconds. Just needs some speed.
In this level you can't let the bridge too high or too low. If the bridge is too low, then use a balloon to let it go upwards, if the balloon is too high, then use a gooball to build to the pipe and let it go down. The solution is here.
OCD: Finish this level in not more than 14 moves. My record: 13 moves.
I think this level is the hardest level in this chapter. The most important thing in this level is that you should build a perfect base first!
A square at the bottom is called a base square. If you build 7-8 base square, you can build to the pipe safely. If you build less than 7 base squares, you need some speed, for at the top of the tower it can easily fall down.
And then build the tower to the pipe:
OCD: Collect at least 68 balls or more. Well, I am an unfortunate person. Just 1 gooball left! My record: 67 on PC. But 74 on my mobile device.
Then, two levels left. However, they are harder in this chapter than the previous levels.
In this level you need to build a longer bridge. If you just build to the right and don't think anymore, you can't beat the level. Have you ever build a bridge on your computer? It's like the way to build.
OCD: Collect at least 38 balls or more. My record: 34. Suggestions are welcomed.
!!! In this level you can't find time insects or skip this level. (Because this is the last level in a chapter)
When you first come to this level, you can see some water at the bottom. It's awful, because the base square always move. So let it stop moving is important. Just connect two sides of the walls.
Then build upwards to the wheels. The wheels give a force of upwards. You needn't to build too high.
Then you can see some eyes. Use them and let the goo tower fiy to the top and you will finish this level.. The eyes are like balloons.
OCD: Finish this level in not more than 42 moves. My record: 39 moves. You needn't use al the eyes, romove some gooballs can reduce the moves you use.
First, use the gooballs on the top and let it fall down to wake up the Ivy gooballs.
And then use the Ivy gooballs to build to the pipe.
OCD: Collect at least 24 balls or more. My record: 22. It's hard to leave 2 gooballs near the pipe. Maybe I should build shorter near the pipe.
Just three balloons. How can we get to the other side. Here is the picture. Move it as the picture shows and do it more times, it will fiy to the other side.
After waking up the gooballs, then fiy back to the pipe in the same way.
OCD: Collect at least 12 balls or more. My record: 10. I just have some mistakes and don't collect enough balls. It's welcomed that you can show your solutions.
Use the balloon gooball to lift the normal gooballs. Attention: Do not touch the biggest fan!
If you build over the fan, the wind blows from the left to the right. Then you build to the pipe, pay attention to the top. Do not touch the fan!
OCD: Collect at least 18 balls or more. My record: 18. First flag in this world!
Just don't let the wind blow your gooballs! 
First use the balloons in the cloud to let the gate open and then use the conveyor and Ivy gooballs to let normal gooballs go to the right. Finally, use the rest baloons to reach the pipe.
OCD: Collect at least 61 balls or more. My record: 80. Cut the conveyor!
Easy level! Just let the base square fly away and then remove the Ivy gooballs.
Finally use the gooball to build to the pipe.
OCD: Finish this level in not more than 21 seconds. My record: 18 seconds. Just needs some speed! Then there are two levels to beat. Let's go to the left side first.
As the description says, it is not a bug, it is a feature. Just leave two Ivy gooballs near the pipe and send the rest gooballs to the pipe. Then quickly remove one gooball to the pipe.
OCD: Finish this level in not more than 13 seconds. My record: 10 seconds. Also needs some speed. When you finish this level, you will get a whistle. Use this can let gooballs go to where you want then to go to.
Now you have to use whistle. Just click a place and at that place will have the sound of whistle and the gooball will trace the way to find the sound. First use the whistle on the left to wake up the gooballs.
And then use it on the right. Finally use the gooballs to build to the pipe.
OCD: Finish this level in not more than 29 seconds. My record: 24 seconds. Also, speed is important.
Now let's go to the other side.
Well, it seems that you can't break the big "Ugly" at the bottom. You have to bubble it up to the top. Like this:
Bubble it to the top and break it into small gooballs and then remove Ivy gooballs to let them faa into the water at the bottom.
OCD: Finish this level in not more than 30 moves. My record: 27 moves. Just think that how to use less moves and bubble higher. And use less moves to let the gooballs go to the bottom of the level.
All the gooballs on the electric tentacle is like the gooballs in the first level in this chapter. It can only connect with one gooball. Use the balloons to let the left side go up and the Beauty will move right.
Do this again more times until the Beauty lands on the right. Then it weill be broken into small gooballs.
Attention: The pipe is black, all kinds (except balloons) of gooballs can enter this pipe.
You can use balloons to let the base square reach the pipe or use a gooball.
OCD: Collect at least 29 balls or more. My record: 32. Sometimes when you click a time insect, the Beauty will bubble and go to the right. So I saved a lot of gooballs.
You can see a caged Beauty on the left and the red pipe on the right. How can the Beauty get out of the cage? You can see a down arrow under the Albino gooballs. That means you should put many gooballs on the box. If the gravity of gooballs is enough, the box will go down and the Beauty will get out of the cage.
Then bubble the Beauty to far right and let it become small pieces. But you should build the passage way first. (Before the Beauty get out of the cage.)
Finally send the red gooballs to the pipe!
OCD: Finish this level in not more than 45 moves. Just make less mistakes and use less moves to bubble the Beauty and send to the pipe. My record: 45 moves.
You can't find timebugs or skip this level, for this level is the last level of a chapter. The video at the biginning tells you that you should you should send different kind of Beauties into different pipes. There are pictures on the pipe.
Make sure that you should bullbe three brown Beauties and then bubble the red Beauty!
Then remove two Ivy gooballs and let the red Beauty go into the wheel gear and let it become small gooballs.
(The music changes) Use the balloons to send the gooballs to the pipe.
OCD: Finish this level in not more than 24 moves. My record: 31 moves. I am thinking an effectine way, just trying. Suggestions are welcomed!
The pipe is hidden by the huge head. And have you found the fire at the bottom? Use the match gooballs to build near the fire.
Then the huge head goes down. You can use the balloon to let the base square go near the pipe.
OCD: Finish this level in not more than 11 moves. Just reduce the moves that use to build to the fire. My record: 11 moves.
Use the match gooball to build like this:
And then build to the fire.And then the Albino gooball square falls down to the pipe.
OCD: Collect at leat 25 balls or more. Match booball can also enter the pipe though they are flamed. My record: 25.
After finishing this level, you have two levels to beat. Let's go the downside way first.
In this level there is a new kind of gooballs. Use this gooball can prevent normal gooballs from being striked. They can be removed and built again.
It's easy to buils to the pipe with these gooballs.
OCD: Collect at least 26 balls or more. The bone gooballs and enter the pipe. My record: 28.
Use the yellow gooball to stick to the first wheel.
And then stick to the second wheel.
Wake up the bone gooballs then stick to the third wheel, use the bone gooballs to prevent gooballs from being striked. Then use a gooball to build to the pipe.
OCD: Finish this level in not more than 9 moves. My record: 11. Solutions are
Also use the sticky gooball to stick to the middle of the water lock.
And remove the stick gooball. Let the base square fiy to the pipe.
OCD: Collect at least 44 balls or more. My record: 44. Just collect all the black gooballs.
Let's go back to the other side.
I'm surprised that the ground can make fire! You can try it.
You should build a small tower. However, there are only match gooballs. So speed is required.Wake up the ren gooballs first.
Then build to the pipe. There are some extra red gooballs over the pipe. So if you have enough time, build higher and wake up them!
OCD: Collect at least 32 balls or more. You should wake up all the red gooballs to finish this. Speed is really required. My record: 24 on PC. But 32 on my mobile device.
The hardest part is that we should to let the bomb go near the walls. Please look the picture. Build like the picture shows and remove the Ivy gooball as the mouse points.
Do it more times until the bomb goes down near the walls. Then catch fire!
Thenthe walls disappear. Use gooballs to connect the base square with the chain on the middle. Finally build to the pipe. You can leave two gooballs near the pipe, but it needs some hard work.
OCD: Collect at least 45 balls or more. I have no idea about how to finish this. My record: 38. Suggestions are welcomed.
As the title says, you have to explode the head, for the pipe is hidden by the head. And you can't touch it. Have you ever seen the bomb on the top? Build a tower near the bomb and wake up it.
As the bomb can touch the head, put it near it and make a fire!
Then the pipe appears. Attention: The pipe can catch any type of gooballs.
OCD: Collect at least 49 balls or more. My record: 55. Just reduce the use of building tower to wake up the bomb and do not let match extra gooballs catch fire.
First you can see the pipe is red. So you have to build to the other side to wake up the gooballs, then put the bombs near the walls. And next, make a fire.
Then let the red gooballs go into the pipe, this is much easier than before. Because you can build from both sides.
OCD: Finish this level in not more than 34 moves. My record: 42. I have the idea, but I haven't finished it.
First put all big black gooballs into the wheen gear. (The black gooballs in this level is called product Z gooballs.)
Then catch a fire! If you get trouble reaching the fire, there are some balloons to help you.
Then all product Z gooballs will all be in fire. And you finish this chapter.
OCD: Finish this level in not more than 12 moves. My record: 13 moves. Suggestions are welcomed.
After you finish this level, World of Goo Corporation will be changed in green. And the background is 3D! And in chapter 4 the background is 3D, too.
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The green gooballs have a special ability: They can be launched from one place to another place. And the square is like normal gooballs. They can be placed.
Launch the green gooballs to the other side.
Then use the square to build to the pipe.
OCD: Finish this level in not more than 9 secomds. My record: 8 seconds. Just needs some speed.
This level needs some work, because you have to choose the right degree to launch the gooballs. First chellenge:
Second chellenge:
The last chellenge:
OCD: Collect at least 13 balls or more. You can't make mistake during launching gooballs and you have to use only one square gooball in the second chellenge. My record: 12.
Have you seen the red liquid under the ground? That will make a normal gooball change into a red virus gooball. A virus gooball can be launched, and it can connect with another virus gooball that has connected.
First, let some green gooballs change into virus gooballs.
Then go to the top connect with the other virus gooballs. Connect them until near the pipe. The virus gooball chain can't touch the wheel gears on both sides.
Finally send the normal gooballs to the pipe. If you make too moch virus gooballs, you can also try to send them to the pipe. (Only in this level)
OCD: Collect at least 13 balls or more. Make no mistakes and no more virus gooballs = 100% OCD. My record: 13.
Launch a green gooball in about this degree:
Then this gooball will wake up the virus gooballs. Then launch the virus gooballs in about this degree to connect with the virus goball at the bottom. The next one will launch as a slower speed than the previous launch.
Finally launch all the gooballs to the chain.
OCD: Collect at least 12 or more balls. Make no mistake = 100% OCD.
If you just build the bridge to the other side, that will hardly success. Use the squares and rectangle to build as a road block.
Then if you build a bridge, that will be much easier than before.
OCD: Finish this level in not more than 22 moves. My record: 17 moves. Just use more rectangles to build as a road block.
Do it as the picture shows It needs some speed. (This is not the only solution. You can use your own and even share with us.)
Then build to the pipe.
OCD: Finish this level in not more than 36 seconds. My record: 26 seconds. Speed!
Then you have two leves to pass. Let's go to the left one first.
Build road blocks! Here are the pictures. First:
Next:
Then:
Finally:
OCD: Collect at least 42 balls or more. In this level virus gooballs can't be collected. So do not leave any green gooballs. (In this level green gooballs have no ability.) My record: 42.
Let's go to the right side.
In this level, balance is the most important. If you lose balance, your goo tower will fall down.
In order to keep balance, so build a horizonal tower first. And then build to the tower first quickly. Once the tower is near the pipe. It won't fall down.
OCD: Collect at least 24 balls or more. My record: 22. Solutions / suggestions are surely welcomed.
You can't pass this level or find timebugs, for MOM's computer will send you a message. Do not use the gooballs in the small computer. They are useless. Actually this is a tower building game. Click an application to create a square. Click a game to create a rectangle.
Build it to the shinning circle at the top and click "Shortcut to MOM". And then "Ask MOM Beta" will open. Ask MOM the third question till the end. MOM will tell you how to do next. Then you will pass this level.
OCD: Finish this level in not more than 15 moves. You can replay this level again and you needn't build to the shinning cirrcle you will pass the level. My record: 12 moves.
Go to World of Goo Corporation and agree an e-mail on the computer. Then the last level of this chapter unlocked.
Launch a green gooball to the fire. It can make a bomb after it touches fire.
Keep doing this and then go to the bottom of this level. Launch the gooballs to the bottom of the gooball chain on the middle, let it touches the fire.
Then there is an information both buttons you can click. Because thay have the same meaning...
Then you will pass the level.
OCD: Finish this level in not more than 7 moves. So hard. My record: 9 moves. Welcome any solutions.
After finishing this level, World of Goo Corporation will be destroyed.
This level is very, very long. But it's not hard. Use the balloons to send the left side up, then make the goo tower longer. (Use the gooballs) Then fall down. Do it again 2 more times.
OCD: Collect at least 16 balls or more. My record: 10. Welcome suggestions!
Let's go to the left first.
Use normal gooballs to build a tower to wake up other gooballs and balloons.
Then go down, make sure that you tower can't touch the wheel gear.
OCD: Collect at least 42 balls or more. My record: 46.
Make sure to build a tower first. Do not build a bridge. The balloon can help you build tower. Build to the cloud on the top.
Then let the tower fall down. It becomes a bridge.
OCD: Collect at least 40 balls or more. My record: 32. Use less balls building the tower.
Use all the fish gooballs and you will finish this level. Then enjoy the video and... the credits.
OCD: This one is mine. -the Sign Painter. That means, you cann't get a fiag in this level, for this level has no OCD.
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