Just saw this on Steam today.
All you have to do is play 1 game to unlock the achievement. Pretty easy.
http://wiki.teamfortress.com/wiki/Black_Rose
Team Fortress 2 "Black Rose"
Receive the free Alliance of Valiant Arms-themed Team Fortress 2 weapon, "Black Rose", by unlocking the "1st One Down" achievement in A.V.A.!*
To receive the free TF2 item, players must create a character and complete their first game to unlock this achievement. (Players who've already unlocked should also receive the item.)
*The "Black Rose" will be available in TF2 later on today.
All you have to do is play 1 game to unlock the achievement. Pretty easy.
http://wiki.teamfortress.com/wiki/Black_Rose















