I dont really have a problem with that, but... I got this achievement:
Roid Rage


Achieved by 386 players.

Juice good! Make strong!
How to get it: Win 100 matches or more with a booster.



But never bought a booster o.0
why did I get?
CHeers.

i got the green thumb. and i almost never play jousting. maybe i have won 100 matches without knowing it. or its just a bug

has the account always been yours? Or did you buy it off of someone? Is there any chance someone else could have used a booster or instaboost on it?

I dont know... maybe I forgot that I bought booster? I dont really believe that...

As Novitech said, if you bought this account from someone, it's possible that the previous user "got this achievement for you".

Anyway, don't really know if not.

Well there are still some tweakings and bugs around these achievement, and if your sure that you didnt earn that achievement then PM nachouru/veb about it, they'll sort it out.