Thorn was the hardest to me because I suck at PvP. Then too my first run through was back when I was 26 or 27 and I was using mostly blue weapons to take on the strike. That was...challenging. Finally found a team to punch through it though. Now though? With VoC, Ice Breaker, and a 331 Arc lmg it's freaking easymode. Knights are still the worst part, but I've finished it 3x now so each char has one. Way easier when everyone is geared to the nines.