This event is so very tricky that i have to use my 2nd character for perfecting this walk through. In every major city you can find the NPC (Baker) who will bake for the cookies that you will need along the event later on.
Together with him, you will notice a group of children formed in a circle near the fountain or in the city's square area
Talk first to the Baker, keep talking to him until he says he wants to know what game the children will be playing.
Then, approach Willem and talk to him after that talk to Johan (Your enemy). After each dialogue of Johan talk to other kids then talk to him again. wait for him to tell you that the baker is already finished on the cookies.
Talk to the baker until he gives you a random number of cookies. It can be 60 pcs, 59 pcs, or 58 pcs.
I guess you already know the rules of Johan's mind game. To refresh, you will need to give cookies to any of the children around the circle. There are 8 kids. They will be getting a minimum of 1 cookie up to 3 cookies depending on what they want. Its automatic so you cannot decide. After that, you will give cookies to Johan he will also decide how many cookies he wants.
Kid A -> Johan -> Kid B -> Johan
You can do repetition in giving cookies to any kid.
The goal is to give or force Johan to take the last piece of cookie that you have in order to obtain the Event reward.
In my experience, Luck is not on my side but I can give you some tips. Here they are:
* Carlen only gets 1 cookie
* Michelle only gets 2 cookies
* Pieter only gets 3 cookies
Note: These 3 kids are your weapon in fighting Johan.
* When Johan force you down to 5 cookies you will lose. Base on my experience.
Your goal is to be the first to get the 49 cookie mark. Meaning you should have 49 cookies before talking to Johan again. Like so:
I got 59 cookies from the baker. I talked to Michelle who took 2 cookies. Now, I have 57.
Johan will get 3 cookies making it 54. Now, talk to Carlen, she will take 1 cookie to make 53.
Johan will take again 3 to make it 50. Now, this is the part I was talking about to make it to 49 cookies. Talk to Carlen to do so.
From here you have now the advantage. I assume you already notice the total of 4 cookies when Johan is winning. Now, use it to win his game. When Johan takes 3 talk to the kid that will take 1, When he takes 2 talk to the kid that will take 2, and When he takes 1 talk to the kid that will take 3 be careful though do not use the same kid as before. Do this and you will win the reward.
As I was saying above about the "Do not use the same kid as before". Here they are, use them alternately in order to win.
Johan - Enemy
Sylvia - Trickster
Carl - Trickster
Alberto - 3
Pieter - 3
Michelle - 2
Willem - 2
Anne - 1
Carlen - 1
Why I label Sylvia and Carl as "Trickster"? because you do not need them and they might lead you in losing the game because they are randomly getting cookies from you which will ruin your calculation.
I am not 100% sure about this one since I'm not sure if the admins will manipulate the system (LoL) but I hope it will help a lot.
The event will end on November 3, 2010. Source