Achievments are tasks you can do to raise your Achievment points.
The higher your achievement points, the higher you're rank on the global rating.
you can check the ranking for achievements here:
http://warofdragons.com/rating.php?rating_id=5&kind=&level=
the highest person in our server have 18k achievement points.
the highest person in the russian server have almost 25k achievement points.
also, you can buy emotions with achievements.
they are not easy to get, but it's great because if you are trying to get achievements, you will pretty much always have stuff to do in game, even if you're bored of hunting/picking.
to go to the achievement page you can press character>achievements, at this page you can find all the achievements you have, the achievements you don't have, or just show all the achievements.
the sub-tab that give you the most is the pets sub-tab, which if u complete, you get 5,055 achievement points (OMG@!)
on the top of the achievement points there are two more tabs, Comparison of achievements, which let you compare the achievements you have with a different person from your own race.
and the shop tab, where you can buy emotions for achievement points, which goes from 200 achievement points to 1000 for one emotion.
the achievement shop can be reseted once every 2 weeks, and then you can change the emotions to others.
the more achievement points you have, the more you can buy.
also, you don't LOSE the achievement points when you buy emotions, you keep ur points, but they are just handled as a cap (lets say i have 1000 achievement points, i can only buy emotions with 1000 achievement points, so if i buy one for 1000 points, ill still have 1000 points, but i won't be able to buy anymore).
if you go to a player profile, you can see how many achievements he have, and how much total points he get from them.