Antlan's Arc

Right, well, let us begin, shall we?

Speak to Antlan and talk to him to begin. He's quite eccentric...as always...
He'll be impulsive, rant about Lenna, ask if she's going to confess to him, complain about being alone even though Zeika and Zure visit him, et cetera.
He also yelled "FOREVER ALONE," in reference to a certain meme....

Talk to him again. Antlan will invite you to...a....random...island...what....

Victoria Lake? Really?
A Soul Eater will attack you. You can fight it, but it might as well be a scripted battle. It'll use Memory on Antlan, killing him in one hit, and the battle will end.
Lenna will do a Solid-Snake esque "ANTLAAAAAAAAAAAAAAAAAAAAAN---" *Plays MGS theme* FISSION MAILED!

...
...

So Lenna drags Antlan back to base, and he recovers after sleeping a bit, but it's revealed that...
HE LOST HIS MEMORY...of Lenna only....
How freaking convenient is that?
Athena will inform you of two things that might restore his memory: The Magical Leaf and the Magical Fruit

MIRACLE FRUIT! YEAAAAH TOUHOU...okay, no.

The Magical Leaf can be found from Ligators, one map east of Kerning. (In FSI, it was the map that preceded the Lost Forest)
The Magical Fruit can be found from Emo Slimes in the Mines. Just walk around the first map.

Go back to Antlan and apply both remedies. Neither will work.

Talk to him again, and you'll be hit with a Branching Path.
Now let's start the flowchart that's at least as complicated as Fate/stay Night's! No, wait, that'd take hours...

Pick "Start over again."

Talk to him again, read the last text scene, talk to him again, and pick "I want to go somewhere!"
Run through the text, and if Antlan knows Phantom Throw, he'll learn Carnival throw.

STOP WITH THE FREAKING CARNIVALS! AGGH!