Hi and welcome to this "Common sense guide". >_>
Okay, what you need for lowering the chance of being found when scamming/robbing a guild bank is:
-A friend with a couple of items that he/she can spam the guild log with.
-A character high-ranked in a guild/allowed to take gold/stuff from the Guild Bank.
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I've already said pretty much all, but for those who don't understand, let me countinue.
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The guild scam/rob/theft:
Invite your friend to the guild, maximize his/her rank. (Your friend NEEDS to be able to set stuff into the bank & withdraw it)
Take everything of value/items that you want from the guild bank. As soon as you've taken everything out that you wants, tell your friend to set in the couple of items that he/she got. As soon as your friend has set in the couple of items, tell him to immediately take them out again. Rinse and repeat until the log is full.
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F.A.Q.
Q: Why should my mate set stuff into the Guild Bank and then take it out again?
A: There's a log in the bank, which is accesable by players, which shows who and what that has taken out items/gold from the guild bank.
Remember to check the log to see if you or your friend has filled the whole log up so you can't see that you/your friend took any of the valuable items.
Q: Can I be banned for this?
A: Yes, you can be banned for this but Blizzard will mostly only look into the case when the guild masters account/Officers account has been scammed, hacked, or whatever it has been. (Comprimised)
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In the World of Warcraft Knowledge database the following has been written about the so called 'Guild Thefts':
"We would like to remind you that it is the responsibility of the Guild Master to manage the guild bank to prevent any theft. The permission system available is sufficient to prevent this and should be explored fully...."
"If nonetheless you are victim of a guild bank theft through an account becomming compromised, only the Guild Master should petition the game masters. We will then investigate the case, but we are not always able to guarantee any reimbursement."
That said, it looks like Blizzard won't bother looking through the case if it wasn't a scammed account.
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Tips & Tricks:
*When you or your friend is going to spam items into/out of the Guild Bank, right-click the item to get them in, and also to take them out. With this you won't have to drag the item from the bag to the guild bank and back.
*You might want to ensure you self even more by spamming the guilds invite/kick logs. This can be done by having your friend inviting and kicking an alt of yours. You probably want to delete both your alt and your friends character after this to prevent account bans even more.
*Your friend wants to bring 5-10 items, maybe even more, so it'll go way faster with spamming the Guild banks logs.
*FOR GODS SAKE, DO THIS AT NIGHTTIME! You don't want to risk some annoying player to yell that you kept inviting/uninviting some player and that your friend spammed the guild log. PLEASE check occasionally if there is any player online, if there is so, watch out! You can check if they're AFK by going to the Guild tab and click the arrow that leads to "Player Status".
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Please notify me if this is a repost, I searched through the posts but couldn't find any. Thank you for viewing my guide and feel free to comment on it and how to improve.
Happy scamming.
-Aurina