Finally, this is what I feel, leveling your core skills to level 50 is NOT hard with drop rate equips. I accomplished 2 of my core skills to level 50 without buying any core at all. As long as you willing to spend 3 weeks of your time everyday on hunting cores you can do it also.
I will recommend you to get 100% drop rate at least to hunt cores in arcane river. I find that there is no difference between 100% drop rate and 400% drop rate. As I tested. I know logically 400% drop rate should drop more cores. I hunted for long hours on 100% drop rate and 400% drop rate, there is no difference at all, I still get approx the same number of cores.
Kill monsters that you can 1 hit KO. More kills = more cores!
In regards to the drop rate, the x1.5, x2 server drop rate is almost NOT effective at all. I hunted lesser cores during the server drop rate. I doubt there is any activation of drop rate during the server drop rate event. I hunted during several server drop rate events, no, it is not effective at all. However, I heard that twin coupon and KK chair is more effective than the server drop rate.
Anyway here is my V matrix, you hunt cores with your main skills (2 of your main skills). For example, I'm a bowmaster, my main skills are hurriance and arrow platter that I always use them to grind monsters. So I get them to lvl 50. The rest of the core skills like arrow bomb is useless for me as I never even use it at all, I exclude those skills from the cores.
I solo-ed C Vellum without any death at all, before this, I am unable to do it! This is the power of core guys, core is an essential now.
