I have spent a lot of hours in the new map, killing a lot of mobs, participating in a lot of events, and never got that achievement to trigger (never saw Zafirah pop). For comparative purposes only, I have seen Aurene "helping" me 4 or 5 times everyday so far.
1) Is "SNIPER'S NEST" a personal trigger? Only you can trigger it, and only for yourself? Or once it triggers for a particular player, all the players around get the ach as well?
2) Does it trigger because of something you dou? because of somewhere you go? Or is it totally random? Such a bad idea in this last case.
3) Is there any way to improve your chances to get it? (be alone, be in group, do events, kill bosses...?)