Secret Arena Location

[Islandi]

Yes, it is:
Negate Jewel - When a team uses a micro-burst or trust charge, occasionally it does not consume the trust gauge. Multi-use: OK

If you are using micro-bursts and trust charges frequently, this Jewel will also come in handy:
Trust Jewel - The amount the trust gauge increases each turn for a team slightly increases. Multi-use: OK

I have 3 of each by the time I reached Forgotten Village.
Be sure to search the 2 fireplaces in a room in the Forgottern Village. There are Jewels hidden there. I think 1 of them is a Trust Jewel.

The tactic here is to use micro-bursts during the battle and end it with a Unison spell (Destruction is my preferred choice) that hits with high numbers of overkills to refill your Trust Gauge.

[Weisteisen]

I see thanks

[Searinox119]

Edit: Islandi already said everything before me.

[Zakier]

Any suggestions on how to avoid her go to sleep attack that swoons the entire party?

[rimrazan147]

There is A way to avoid insta-kill attack(go to sleep)it was to use re-raise gem at Stella,Zack and Felix(unfortunenately you can't escape an attack that would make you swoon immediatly)and after that make maidame Curie to use A skill that Will reduce all your plus stat(like re-raise,stat up,and reflect)and make Stella use skill that called:look over here,and make zack and uriel(teammate)to use full-counter(beware go to sleep is not A MAGIC SKILL NOR A PHYSICAL SKILL,IT WAS MORE LIKE A FORCED SKILL OR PUNISHMENT SKILL) with you being hit with that all your party Will immediatly resurrected

[rimrazan147]

Bloody maidame Curie weakness
1.maidame Curie never use a same skill at once(it was impossible for her)
2.after you make maidame Curie use A certain skill that will reduce all your parameter enhancing effect(+stat,like re-raise,reflect and stat up)maidame Curie Will not use that skill for 2-3 turn(this is A key of winning)
3.when maidame Curie use A skill,like go to sleep,countdown skill,and +stat rescuing skill it will take A long time for maidame Curie to take A turn(as long as Stella has 5000 status it's all possibble)
4.when maidame Curie use A so called near death turn-passive type skill that Will make you can't defeat maidame Curie with A hit count,her can't use go to sleep skill and +stat reducing skill(finally you can cool your brain and yourself down)you need to make maidame Curie never-ever take A turn(since you using A final weapon of course you can do it)
5.when near death skill active YOU JUST CAN DEFEAT MAIDAME CURIE WITH NORMAL ATTACK WHAT'S MORE IT WAS A HIT AND DAMAGE,from 1 until 120-130 and you win!!!!

[rimrazan147]

Reward for defeating maidame Curie
1.maidame medal
2.B.attack Jewel
If you expect anything good i am soooo sorry since the reality is harsh(evil laugh)
( i using try using enah and Jolie Curie as A buddy)