Anyone else wasting alot of energy trying to complete Artifact Challenge  6.1, 6.2, & 6.3?

Granted you only spend 4 energy per try.  In the Sewers of Annoc, on normal.  The problem is that getting a 3☆ Artifact from there is a rather low percentage.  When you add on that the  only primary stat allowed is ATK (%), it is damn near impossible.  This relies on sheer luck only.  No skills, no.....anything else.  I've already used over 1k in energy on 6.1 to no avail.  I do get 3☆ Artifacts on occasion.  All were DEF for primary except 1, which was ATK.  Not ATK (%).