Main idea is that you want:
Fire (90-max) -
Because this is where you get most of your attack-power from. Although the skills are stuck at 69 you still get more attack power from the mastery itself (1% each time you up it)
Bicheon (68-70) -
Just to get all the skills that you'll use in combination with your imbue,
Lightning (68-70) -
To get all the buffs.. the +mag atk% and +speed% buffs are a must
This means that you have 300-(90+70+70)=70 points left. Options on where to put it: Pacheon, Heuksel and Cold. Pacheon isn't really a good idea. You get it for the +attack rating, but at higher lvls you can use alchemy for that.
So that leaves 2 options: heuksel and cold.
Heuksel: you won't be able to use the active skills with a sword.. so you'll get it for the passive, which gives 1k hp.
Cold: most of the players are immune to cold at higher lvls, so the main reason to take this is the buff+passive which together give +68 phy defense.
Decide for yourself
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