i 2 tap and then hold right in the middle of the white line on the left. getting everything to line up perfectly on the boss fight is so hard, and i couldn't get a consistent set up for it, i just jump when he passes the middle of the empty space and drift a bit before instashielding, do the same suspended jump for the second hit, but hold right quickly so that i land close to him, then do 2 small jumping instashields and pray