Azyleo’s Secret Arena Guide
Written by Azyleo
Unlocking the Secret Arena
The Secret Arena is located in the Forgotten Village, and becomes available after you complete the first ending (and find all 11 sprites).
Go to the right side of the village (the side that's been closed all this time). Inside, you'll find Maidame Curie and a couple of maids.
There are four battles available - two on the left and two on the right.
Gate A (Savage Kitties)

Cost: 54000 Gold
Boss: Leon
HP:
Prize:620(Non-Orb)
Boss Level: 200
Required Level: 240+
Recommended Unisons: Mama's Deck, Decided Punishment, Last Punishment (Two Characters Should Have This), Eternal Providence, Heal X3.
Some Requirements: Be Level 240+, have all above Unisons, Izayoi should have Maid Brand, and any one other character having Maid Weapons. 2 or more characters should have a Parameter Ring equipped.
Boss Skills: Rage(Attack Down, chance of rage), Claw, Double Claw(Defence 1 Rank Down per Hit), Magic Rain(AOE Attack)(Hits Every enemy and any random parameter 1 rank down).
WARNING: THIS BOSS TAKES 2 TURNS PER TURN, MEANING HE WILL ATTACK YOU TWICE EVERY TURN.
Strategy:
This Boss Battle really isn't much, as either you will win or lose in under 4 turns. If you have Iazyoi with Maid Brand, and the Parameter Ring equipped, you will always strike first. Use Eternal Providence and Mama's Deck(For 2 Rank UP All Parameter's for all characters), Heal Gnome on the character.
Heal when required. Use Last Punishment only when you have full HP.
Make sure to Rank Down all Leon's parameters for taking him down much faster.
Izayoi's Divine Slash and Last Punishments works wonders, provided you Have the required HP.
Leon has a magic skill called Magic Rain, which does MASSIVE DAMAGE to anyone who receives it, plus any random parameter 1 rank down. He can also use this 2 times per turn. I recommend to always heal when he uses it.
Even if you're 40 or 50 levels above him, his physical attacks still do 2000+ damage per hit, and magical attacks do 8000-15000+ damage.
Gate B (No Tougher Sister)
Cost: 98000 Gold

Boss: Jolie Curie
HP:
Prize: Gem Set
Boss Level: 300
Required Level: 380+
Recommended Unisons: Eternal Providence, Last Punishment, Heal X3, Decided Punishment.
Some Requirements: Izayoi should have Maid Brand, Freya should have Laundry Pole equipped. All characters should have Parameter Ring equipped.
Skills:Miracle Slap, Slap, Full-Round Slap, Heavy Crash, Oh My, Quite You, Let Me Serve You, Dynamic Service.
Strategy:
Jolie Curie always attacks twice per turn. She will always use "Let Me Serve You" and "Oh My" on her first turn, Slap and Majestic Slap on her second turn, and Quiet You and Any Attack on her third turn.
Fourth and fifth turns are healing phases for you (she may use Oh My here, but its quite rare, she mostly uses normal attacks here).
On her sixth turn, she uses "Heavy Crash," which causes Random Ailment and Countdown to all characters. Her seventh turn is always Dramatic Service, and the eighth turn is another healing phase.
After that, she just repeats the same moves over again.
Your best chance to win is to defeat her before her seventh phase ultimate attack "Dramatic Service" which reduces all your character's HP and MP to 1.
Gate M (Maidame in Her 20s)
Cost: 295000 Gold
Boss: Maidame Curie
HP:
Prize: First Time Reward:Asdivine Dios Points x12.
Boss Level: 500
Required Level: 600+, 700+(If you want to toy with her that is)
Recommended Unisons: Dispel, Dancing Read, Deadly Embrace, Starlight Gift, All Heal, Hi-Revive
Some Requirements: All Maid Weapons and Maid's Armor equipped. Parameter Ring on all characters.
Skills: Miracle Slap(Single) ,Let Me Serve You(All), Box Tray(All Enemies), Tray Laser( Single ), Look Out Below( Single ), Heavy Crash( All Enemies), Ultimate Inferno( All Enemies).
Strategy:
Maidame Curie is not like her sister at all. She has no attack phases, and including her own, has all the skills her sister has.
The thing is her HP is quite low for a Level 500 boss, however her attack strength alone is a nightmare (along with her skills).
Beware of her Heavy Crash (attacks all enemies and inflicts multiple status effects including countdown) and Ultimate Inferno (HP and MP 1 for all enemies, and all parameters down 2 ranks for all). Miracle Slap (inflicts various status effects including virus on one enemy) is another one to be wary of.
Let me Serve you is a skill she uses in the beginning of battle, as well as after Heavy Crash (heals any status effects, and parameters 2 ranks up for all. Also this does not heal HP, MP and Count down).
She Will use Let Me Serve You! on the first turn, after which she can follow up with any of the above skills except Heavy Crash.
Use Dispel to remove her parameters. And just like any boss fight her. When she uses Heavy Crash and Box Tray heal and revive accordingly. When she uses Ultimate Inferno (which is followed up by a normal attack) use Deadly Embrace or Dancing Read to heal yourself and then either use an item or use Revive Cure, If you are really in a pinch you can use the unison Hi-Revive. Use Items if you need to bring your MP back up. Then keep hitting her until she is dead.
She is not much of a boss. Only cheap skills aside, she is not worth fretting over.