Written by MSG Commander
Once inside the castle, Harvey and Amelia lose their disguises, and Amelia says you should head to her room to plan your next move.
You can sort of explore the castle while you're in here, but if you approach any of the guards, they basically tell you that you can't go that way.
Get the first 6 treasures, and then take the stairs in the north to Amelia's room. (The last treasure is in her room.)
As Harvey and Amelia are talking, the impostor comes in and sees them. Knowing she's been caught, she makes a run for it, so now you have to track her down. (But first, get the treasure in Amelia's room.)
You'll find the impostor at the entrance to the throne room. Select "It's time to unmask her!" and then watch the scene to learn the impostor's true identity, and the reason why it could never be revealed to Amelia...
Meanwhile you also learn that Duncan started this whole ordeal so that he could take over the kingdom. Then, you get to fight him.
Duncan, Luminia Soldier x2
- Drop: Charge Jelly x2, Economizer Jewel
For this battle, take out the soldiers first, then focus everything you've got on Duncan.
You can use magic or skills on the soldiers (heck, you can even use your regular attacks on the soldiers), but I recommend saving the expensive skills for Duncan.
I had Amelia use Attack Down on Duncan to lower his ATK and INT, and Harvey use Triple Strike.
(You can also use Harvey's Trust Gauge, Tempest Cross, to really speed things up. It probably won't kill Duncan outright, but it'll come darn close.)
After the battle, Duncan summons the Shadow Deity to help him.
He orders the Shadow Deity to kill your party, but... the Shadow Deity kills Duncan instead, and then there's another Boss battle.
- Drop: Alto Tablet
Since Stone Colossus is Shadow-based, have Amelia use Light Thunder as much as possible.
Meanwhile Harvey's Triple Strike will be his most powerful attack.
If Stone Colossus uses Full Guard, have Harvey switch over to magic attacks.
Make sure to watch everyone's health in this battle, as Stone Colossus can do a lot more damage than Duncan did.
Stone Colossus is strong, but as long as you keep Harvey and Amelia alive you should be able to win this battle.
After the Boss Battles
Afterwards, the impostor charges the Stone Colossus and learns her first enemey skill: Ram.
Then the soldiers come in, and Amelia sets things back in order in the castle. However, there's some concern about the Shadow Deity having appeared and murdered Duncan, so the ministers suggest that you travel to Tenebrant and see if you can find out more about the Shadow Deity's motives.
Harvey and Lucile agree to accompany Amelia, and Lucile joins your party.
Before you can leave for Tenebrant, though, you still need to do a few things in Luminia City.
First, exit the throne room to learn more about how Lucile learns skills. Then, exit the castle, and after the dialogue, go to the Inn and talk to Olivia. After that, you should explore the Chancellor's Mansion for some treasure and another learnable skill (it's not part of the story, but it's worth exploring, now that it's open.)
Remember to equip Lucile with a weapon, armor and jewels! I recommend the Skill Doubler Jewel and the Titan Jewel, but you can use whatever you want.
04 Monster Investigation - talk to Calvin outside the throne room (available after completing the story quests in the castle)
Map and treasure list by Searinox119
T1 - Blue Jewel
T2 - Yellow Jewel
T3 - Weed Gem
T4 - Skill Doubler Jewel
T5 - Heal Potion x3
T6 - Light Rod +17 (Sleep 20% Rage 20% HP 16%)
T7 - Prickly Cactus
Lucile learns Ram and Molecular automatically as part of the storyline.
But, if you talk to the Luminia Soldier in the middle of the room that leads to the east entrance, he'll teach her Transform.
The dungeon area in Luminia Castle is now accessible. (Well, once you have Lucile in your party, and then exit Tenebrant City and re-enter, then, it's accessible.)
There are three treasures in the dungeon, all in secret passages.
T1 - Four-Leaf Clover x2
T2 - Long Sword +90 (SPD 40% EXP 30% Countdown 30% Critical 30%)
T3 - Alto Tablet x5
Learnable Skill Reward
If you talk to the Luminia Soldier who taught Lucile Transform on your first playthrough, this time around he'll give you an Experience Trunk.