OK so you've all seen them people linking the achievements they've done, and it shows on the tooltip when you click it "Achevement completed by ____ on x-x-xx", well the thing is, like item links the server doesnt actually validate the contents of a link it just validates that it is a legal link, meaning of course that you can make up one that says you earned the Scarab lord achievement (for example) on the 15th of October, and confuse the hell out of your guild mates.
HOW
Step 1: Gathering information. Its not as simple as just copy/paste some code and bam it works, you need to get the following things:
1. Your characters GUID. I don't want to sit here all night explaining what a GUID is etc, just run this:
Code:
/script ChatFrame1:AddMessage(UnitGUID("PLAYER"))
it should look something like this: , chop off the 0x and make a note of this, you'll need it later
2. The id and name of the achievement you want to use. Best way for that is to look it up on wowhead or something similar. On wowhead, the URL will look something like hxxp://www.wowhead.com/?achievement=1234 and its that 1234 that you need, as well as the exact achivement name.
3. The date for your achievement, if its something like Scarab Lord, then pick the patch date, which is when it would have been awarded, otherwise, pick whatever date you want after the patch date.
Step 2: The magic bit
Substitute the following information in where marked, and run this command:
1234 = Achievement ID
0000000000000001 = Character's GUID (Yes you should put all the zeros in that you got from the command above)
12 = Date (Month)
31 = Date (Day)
8 = Date (year, last digit)
Scarab Lord = Achievement Name
Code:
/script ChatFrame1:AddMessage("\124cffffff00\124Hachievement:1234:0000000000000001:1:12:31:8:4294967295:4294967295:4294967295:4294967295\124h[Scarab Lord]\124h\124r")
From there, shift click it into whatever chat message you want and it should work.
If you get d/ced or your guild decides to kick you for whatever, please don't blame me.
And one final point: you;re forging a link for an achievement, you're not forging the actual achievement, as far as the game is concerned this has no effect on what you've completed, and anyone comparing achievements to you will see what you have/haven't done anyway.
EDIT: fixed link, had a C instead of an R at the end