if u want upgrade ur weapon via other blue stuff, some people told me buy 36 lvl blue weapons cuse its cheapr , u need like 40-50 weapons who cost like 5silver each and 1 -5 cooper per +, .so buying those weapons its like 3-4gold lets say, but if u would use 45 blue weapons its 10 silver per + weapons u get from dungeons u anyway make daily…so in the end its almost same thing.
Best way to level up your weapon stages beyond siren is to just transmute element of luck, most cost efficient and want to Buy Blade And Soul Gold. Then if you have a tiny bit of xp left to fill, feed it in with brightstone or dokumo blue weapon (they give the most xp of all blue weapon fodder).
Blue weapon still ok to upgrade awakened siren/true siren… heck you can even use Purples (make sure its Pirate/Warrior 7fl mushin/Blackwyrm weapons) those purples give the most Maximum exp (though its rng… if your lucky you get 1 lvl worth of upgrade with just 1purple + 2 soulstone)
Awakened pirate/true pirate (its better to transmute at this stage) and if your lucky you might get 4pcs Elder Dragon Element (they are tradeable and you can sell em for 4-6g per piece)… though as far as i know… Elder dragon only has chance to Pop up if you transmaute the Bundle one (the one that needs 15ss + 1.5g)
Do the transmute elements give more exp than the normal element of luck that you can get from the daily dash atm? Because those give 1/4 to half a lvl at awakened siren stage, if those are the same it’s not worth Blade & Soul Items. Transmuting element package with current soulstone prices costs more than 6 gold which in the worst case would be 3/4 of a lvl and in the best case 3 lvls. Feeding blues costs around 1-2 gold per lvl thus is the better choice if those elements are the same..
Why would you purchase everything? You can make 19 soulstones (21 with the PK quest) from doing faction dailies (Woods, Beach and ToE daily) not to mention SS from PvP. That’s enough to transmute an element package (which do provide more experience than Elements of Luck as Ive noticed, especially if you receive the Elder Element). How much so, I don’t remember. In the long run, it’s far more expensive to feed blues into the weapon.