On entering the Royal Valley of Ambervale, Marche meets Cid, who has not yet located Mewt. The two find Babus lying unconscious on the ground, but an unknown voice says that he is not dead.
Llednar appears and blocks your path. Cid brings out his anti-law that Marche helped him create. This powerful anti-law removes Llednar's invincibility. Now Marche must fight Llednar.
Encounter: Llednar Twem
Objective: Defeat Llednar
It would be wise to bring a healer with you into this battle. You are quite possibly going to have a lot of KOs in your party, so prepare accordingly to recover as quickly as you can from KOs.
The Ninja uses Double Sword and is therefore very dangerous with physical damage. Keeping your distance might help you be safe from that, but he also has Veils that can cause status ailments from afar.
The Gunner is dangerous with abilities like Charmshot and Stopshot, but the good news is that he doesn't have the Concentrate ability, so he can't shoot that well from far off, and better yet, he will be pretty powerless if blinded.
There's an Assassin, but she doesn't have Last Breath. She does have Nightmare and Rockseal, so be prepared to deal with those.
The Alchemist has Death, which causes instant KO, and Flare, which does huge damage. This Alchemist can also inflict Frogshape.
The Illusionist has elemental damage attacks that affect everyone in the area.
I recommend bringing down the Ninja and the Alchemist if you can, because they're sure to be the most dangerous.
As for Llednar himself, he has the very powerful Omega ability, and there's no law to protect you from that, and it's likely to instantly KO a unit. All you can do is be prepared to revive from KO a lot and focus your energies on Llednar, disposing of the Ninja and Alchemist if necessary. Llednar also can do Life Render on a unit, which inflicts Doom, and he can push back surrounding units with Furycircle.
After Llednar's defeat, he will turn to stone, and crumble.
Now, Babus awakens and says that Mewt and the Queen are inside. Babus is pretty severely injured, but he still tries to walk over to Cid, who says that Babus needs to stay behind. Cid apologizes that he did not get there sooner to protect Babus.
Babus begs you to help the prince, and Marche assures him that Mewt will listen to them this time.
Marche and Cid enter the palace. Remedi is there, and says that she is sure that Marche still hasn't fully let go of this world, because he has everything he wants here, which means that the real Marche is here in this world. Marche says that it's true that he wanted those things, but he realizes that even though the real world is lacking in some ways, he knows that he wants to go back because the real Marche doesn't depend on the world he's in. Marche begs to talk to Mewt.
Remedi asks what Mewt really wants, and he appears in the palm of the statue's hand. Remedi (rather manipulatively) asks if Mewt wants her to leave, and of course he says no. Mewt then disappears again, and Remedi tells you and Cid to leave, because that is Mewt's wish. Then Remedi's dress transforms into a battle outfit and she wields a scythe-like weapon, making a copy of Adrammelech and Famfrit appear (these creatures are known as Dephs).
In surprise, Cid asks if Remedi is another part of Mewt, too. Remedi rather cryptically replies that she is the fulfiller of wishes, and that both Mewt and Marche still wish for this world to exist. Marche doesn't deny that, but he's through with living a dream.
Now you need to choose your units. Cid will oversee the battle as Judgemaster.
This version of Famfrit is a vastly leveled-up version of the Totema you fought before. Breath of God causes extensive damage, Demi halves a unit's HP, Lightspeed is an attack that can't be blocked by R-Abilities, Presence damages and knocks back.
Adrammelech also has Lightspeed, and Firestream is a fire breath attack. Howl of Rage reduces nearby units' speed.
The Battle Queen will only use physical attacks, but these are likely to do an instant KO, so take down the Dephs and then go for her, being careful to revive and heal up as often as you can.
When she is defeated, she calls to Mewt. Marche and Cid try to talk to him. All of Mewt's fears about the real world go through his mind: being picked on by classmates, being ashamed of his dad, and begging his mom not to leave. Marche asks Mewt to go home with him, and Mewt says that part of him understands, but he still wants to stay in this world.
The Battle Queen then says that she can create worlds from the wishes of others, and she transforms into a blue, floating creature called a Li-grim. It is the essence of all of the wishes that created this world. Marche realizes that this means that if the Li-grim can be defeated, they can go home.
The Li-grim makes two more Dephs appear, this time both copies of Mateus. This is the very last battle!
The Mateuses can do Breath of God, Thundaga, Star Cross (a holy spell that affects all), and Spellbind (which does damage and inflicts Slow).
The Li-grim has the Lawshift ability, which can change the laws at random. Be really careful to pay attention to what laws are in effect for a given turn. Cid can't do anything about it. Amber Gleam dispels any status improvements that are in effect. She can also do Llednar's Omega spell, and an even more destructive Alpha spell. Magi is a powerfully damaging spell and Descent summons a random Totema.
Your best strategy here is to go all out on the Li-grim, keeping the Mateuses at bay. The quicker you get this battle over with, the less time the Li-grim has to break out her really damaging spells.
Once you defeat her, this world disappears and you get to watch the ending. Congratulations!