Seriously ridiculous quest. Especially when you fight Bennet. I run out of time which is stupid, next to the : I need 200+ HP pots, have to use draughts and Elixers still get stupid amounts of damage with 350 AP. This is just not fun anymore and downright frustrating. I have 254 AP, maybe not the best, but man no just no.

Bennet needs to be toned down severly. 

Pit of the Undying is AP capped. You can do 5 AP and do just as much damage as 254 AP.

So it's not your gear. Just need to get better. (You can get more damage by stacking +monster and +human damage though)

Bennet is a tough one. A tip: When she creates the clones, you can tell which is the real one by moving through her. The real one blocks you, but you will pass through the clones. Then just nuke the real one.

She loves to CC you from range, use your FG and SA gap closers and then go to town when you get to melee range.

Good luck!

Yeah I do the collision trick. But I still cannot kill her in time. 

you just need to git gud

I feel Melee characters have an advantage here against Bennet.

About the best way to tell which is the real one, is to be near her and her clones, and try to go through them. Which is fine, except Wizard, Archer, Ranger, Tamer, and Shai have the slowest recovery from Stun and Knockdown. (Berserker has the fastest - Everyone else is average)
Not sure about Sage and Hash as they were added afterwards

On my Wizard, I've tried having a fairy auto-pot and do the phase-through trick, and this makes it a great technique for staying alive while doing considerable damage. However, the 10 minute timer on her seems short in comparison with the other Bosses. I usually get her down to 1/4 health left. With the longer recovery time, by the time one clone knocks you down you're just playing an evasion game - With 1v1s this is usually doable, but it's beyond challenging with 3.

If the timer was longer, or the recovery animation was removed for the rest of the classes, then the system would be a lot better.