"Turn a Blind Eye - Cure blindness"
This achievement is obtained in Orobas Fjords, simply complete the quest "Sight for Sore Eyes". To gain this quest, talk to the man sat on the rock next to the teleporter which takes you to the fort; introduced with a little video when you fly near it. If you manage to land on part of the hill on the right side of the fort, then jump down on to the fort's dock (Like I did) you can just use the teleporter before going in to the fort and it will teleport you to where the blind man can be found.
To complete the quest, you have to give the man 2 malachite gems. The way to get these is to plan ahead and buy the gems from Lamotte the merchant in the Broken Valley Village, as he sells 2 of them. Malachite gems are really few and far between, so make sure you get both of these gems before you claim the battle tower for your own. As the 2 I have mentioned are the only ones I know the location of.
-- EDIT -- Lil Miss Cherry was kind enough to supply a link to the location of all known Malachite Gems, head over to http://divinity.wikia.com/wiki/Malachite_Gem
if you are having trouble finding them for this quest.
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