if you wanna assassinate an assassin, all you have to do is to know the assassin youre facing. as stated earlier, sinx got 3 build, crit,SB and thana/IP build. all you have is to counter them. i personally uses OL+tao vs sinx(crit build) and 2skoll vs IP/Thana and thana SB sinx...
and also use box of sunlight for you to see where they go.