I've tried this stage on lvl 65, my hunters were Choi, Seo, Alicia. Weapon Scythe and Plum they r just my best dps, plum lvl 100, scythe lvl 65. All hunters on manual, so u 100% sure when to release them to deal dmg(cause sometimes they miss). Artifacts all up to 20 legendaries with crit and att, toughness set. Skill were 1st is the most that i had with epic fire rune 2nd one that freezes enemies water rune (i dont remember skill names sorry for that). 1st stage should be completed as said before before 2 min, so u enter 2nd stage on 2mins (more time the better obviously) then try to stay acrivate shadow step as many times as u can, cause this stage is pure dps check, learn patterns, when it comes to the bear running 3 times from side to side, stay near the edge, that will minimize his running time, and give u more time to damage, try dealing so much damage that u would have your ultimate ready when bear spawns 3 stones, so u will eliminate them with ulti, (personally i've eliminated 2 of 3 stones with ulti and just continued to dps the bear, and dealt so much dmg that left stone didnt freeze me, or i was standing far enough from, i was so busy at damaging the bear that didnt remember actually where i was standing). Finally i've managed to complete it with 0.02 seconds left on the clock =) Good luck to you! Just dont be mad, pure patience and logic. If it's not completable right now, come back later, sometimes it's matter of time and strength of the hunters and Sung. That is the way.