Greak: Memories of Azur

Do this achievement with Ankar the following way:

Shortly after Raydel (3rd char) is introduced, you will be reunited with your siblings.
(There is a save point on the way to your siblings, use this in case you need to restart the battle.)
Greak will be stunned on the floor and Adara will be waiting for you ... as well as the Boss Ankar.

When the battle starts, immediately use your shield to guard all the time. Switch to Adara and move her all the way to the left to avoid her being attacked.
Now switch back to Raydel and keep on guarding all the time.
Ankar has three moves:
- jumping around with his shield which can be easily avoided. If you jumps into you, you will take damage and have to restart from your savepoint.
- jumping to the wall and throwing his shield. This is easily blocked and does no damage as long as you guard.
- and finally rushing you. This is the key to defeating him because when he rushes you while guarding, both of you will be thrown to the floor. Now keep pressing A fast to recover and move in to attack him fast. Do this around 5 times and he will be defeated. After he gets his shield back, switch back to guarding and lure him into rushing you again.

Note that he will rush you when you keep your distance. Also make sure not to move too far to the left as he may start to attack Adara.