Frostfang Barioth equipment & material!
Unlike other series skills equipment, Frostfang Barioth's armor activate its series skill only with 1 piece. Punishing Draw for 1 piece, Slugger Secret for 3 pieces.
This series skill fits very well with GS. GS's draw attack inflicts stun (but not often) so that you can strike the charge attack easier. Frostfang Barioth is slower than the original, I think it's even easier than the original. If you successfully hunt alatreon solo, this quest is a piece of cake.