Me and two LS mates just did this. Drg84 (me), Pld85 and Blu71. Hit red HP a few times but that's only because it spammed 1000 needles 8 times in a 2 minute fight. Used Angon and Warcry (no berserk just in case) and whenever I used Penta Thrust I hit for 1500+ dmg which accounted for about 4-5% of its HP so it has a lot of it.
Overall a pretty easy fight.