As you can see from the picture, there is a red book that when you hover over it, your same skill(and same move) will become stronger... In this case in my Blade Master, it increases the Crit and extra Damage.
The condition to unlock this skill is written below, "Available when you "Lightning Draw - Volume 2""
So you need to have that achievement to complete it.
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Press U for achieve, under Characters > Skills, you can see a list of achievement.
Look carefully for the achievement you need.
There are 2 different Lightning Draw Achievement here, so you will need to check carefully!
Hongmoon Secret Technique Lightning Draw unlocks my Searing Slash move 2
Lightning Draw - Volume 2 unlock my Searing Slash Move 1 and 3, as you can see from the first picture, what I want is Move 3.
Thus, I need is Lightning Draw Volume 2 achievement, which needs me to use(just right click) an item called Retrieved Hongmoon Secret Technique - Volume 4
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For this particular Secret Technique, there is 4 ways to obtain it
1) Naryu Foundry
2) Zen Bean Trader
3) Battleground Trader
4) F5 Market
Personally, if you ever saw one that is tradeable version, I would recommend selling them. I have no idea where to find some of the tradeable version, because for this, I know Naryu Foundry has drop the untradable version.
They are very rare thus I do not have a lot of personal experience in them.
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