i have alot rare normal legend lol. it been a month i guess.. i just farm on floor 150-200 and repeat. i dont need to be on high floor since every eternal item i get will be converted to crystal except some eternal that i want lol. just farm with nadroji. max luck, max i.Drop it actually really help. And for me it usually take 2-3 same rare legend when i craft. u know when obsidian give crystal affix, it not always give what u want, so yeah the reject will be converted or if it can be used in other build, i will keep, and proceed with second item until i get what crystal affix i want. So basicly for 1 item i craft it usually need 2-3 same item, 2-3 obsidian. and the rest i can kyanite if it give not needed affix.