To unlock this sub scenario you must first complete Grapp Keep. After you've recovered the toxin sample, return to Eisen Bridge and watch the cut scene. That done, speak to Commander Goodman again. Select 'What is that?' to begin the sub scenario.
- Watch the cut scene at the Eisen Bridge. You'll be blocked from attacking the girl who's causing all the trouble. Stupid dramatic singers.
- Return to the Eschalot and hop in. Ride it back to Grandship. (You might want to turn your encounters off for this mission. Just saying, it takes you aaaaaaaall over the place.)
- Check out the bar in the lower parts of Grandship. The proprietor will mention the sirens' song. She'll also say that you need to speak to the elders on the ship for more info.
- Talk to the old man to the left of the proprietor. He'll basically tell you to go to Ancheim.
- Make the long trip to the desert city and run to the giant clock near the palace. An old man here will send you next to Caldisla.
- Another long trip, though not as long. Check the southern ramparts of the city for an old woman. She'll tell you... to head to Florem. Oi.
- Trip to Florem. Head into the northern half of the city and approach the stage in the rear. The man with the wispy hair up here is the next person on your checklist, and he'll tell you to go to Hartschild.
- Across the continents. Run to the fountain and you'll find another person out front, a woman. She'll provide some more info... aaaaaaand tell you to head to Grandship. Good lord.
- Walk walk walk, sail sail sail. Return to Grandship and speak to the propreitor again. She'll give you a baton. (Why couldn't you have resolved all that just by talking to this stupid woman in the first stupid place?)
- Back to the Eisen Bridge. Speak to the commander and ask to do battle with Praline again. This time you'll get to battle her properly.
Praline, Black Blade, Black Axefighter
This is a really difficult battle if you don't have all-hitting attacks. Praline herself is not that dangerous - offensively all she'll do is hit you with a weak physical attack. Problem is, her true role in battle is to act as a buffer for her bodyguards, the Blade and the Axefighter, who can deal a lot of damage to your party. She's very good at this, granting them extra attack power and a bump to their BP. These two will either attack your party physically for crazy amounts of damage, cause confusion, or lower your physical defense so they can deal even more damage. Ouch.
The key to victory here is to eradicate the two bodyguards whenever Praline brings them onto the stage. Have two of your characters ready with area attacks that can whittle down their poor HP counts immediately after they appear. The other two characters can focus on bringing down Praline herself, or healing up wounds incurred from the appearance of more bodyguards. Praline will constantly summon new fighters in to help her, but each time she does they'll appear with no buffs - very much to your advantage. Keep up the pressure on Praline and guards alike and you will, eventually, succeed.
- Beating Praline (notice that she's, like, the only side quest boss character who doesn't outright die?) will earn you the Performer asterisk, allowing you to transform your characters into buffing wonders. You'll only ever need one of these characters at a time, granted, but put beside physical fighters Performers are fantastic support characters.