Sins Forums
I got talking with one of my friends who is a big achievement collector on Xbox 360, PS3 and WoW, and he got me wondering: do the ingame achievements in SINS unlock anything, or otherwise do anything to or for the player, aside from announce completion of said task?
Nope. The setting file that records which achievements you have is unencrypted, so you can open it up in notepad and "unlock" the achievements that way 
It keeps record of it. Unfortunately, it's only on your computer (and you can actually edit the file manually, if it makes you feel better). You can spend your time collecting them for your own pleasure like on the other systems, but you can't really show them off - Not that anyone cares too much.
Of course, achievments on the systems you mention don't actually do anything, either. They just give you "points" that demonstrate how much time you've spent playing the game ...and how susceptible you are to getting an addiction.
In summary, they're just for fun.
I knew that - the part about the addiction. He has it, and it can be infuriating But thanks for the heads-up!
There are also informal online multiplayer achievements:
Become first pick in the 5v5 pug matches.
Obtain an excellent playing record, such as 20 games played, 20 wins.
Record 500 games played online under a single name.
Record 1000 games played online under a single name (the John James Award).
Win a locked teams FFA with 6 players or more.
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