Guild Wars 2

I started doing episode 6 on the same day it came out, with my ele. I reached the hideout, and didn’t even know the statues could be destroyed until I caught one by accident, and got an achievement for it (grafitti artist). I had a quick look through the achievs, noted that there was one for destroying all of them (art critic), looked for a guide (there wasn’t one up yet), and set about finding all of them manually. Found and destroyed 17 statues, no achiev, figured I must have missed one, spent ages looking. still didn’t find any more, figured i’d get the achiev once a guide went up and gave up on it.

Today, I did the same instance with my thief, referring to the dulfy guide to be sure I got all of them. All 17 statues destroyed, still no achievement. Is there some particular way i’m supposed to destroy them, or is the achievement bugged?