was thinking of levelling up to at least 91 rc...is it still good for double nats to make huge amount of profit ? A friend of mine with 99rc told me that he is not doing well lately with the drop of the nats....is it best to use summoning spirit graahks or abyss ?

For crafting natures, the graahk is best. You can do about 3k ess/hour at 75+ rc using a graahk if you focus.

 

 

 

That's (6k*230) - (3k*140) - (20*1k [super energies]) - (1.2*5k [graahk pouch])= 934k profit/hour at 91 rc.

 

 

 

The best way to get 91 is probably deaths via abyss 68-75, zmi 75-82 and either astrals or zmi 82-91. Use an abyssal familiar while crafting and use super energies.