I'm pretty sure that most of the DLC was the multiplayer, and the Bonus missions. You get the Bonus Missions unlocked by playing through the story. I'm not sure how far you need to get to unlock what missions, but they don't unlock quickly (which is good, cause they're friggin impossibly hard when you first unlock them).
Not sure about DLC costumes being included, I haven't heard anything about that. Maybe someone else can clarify? If they are included, assuming you unlock them like you do the rest of the costumes, then you'll unlock them as you progress through the story.
Found this out on the web. don't know if this helps.
Org link :http://xseedgames.com/forums/showthread.php?2428-Ragnarok-Odyssey-DLC-List!
Ragnarok Odyssey DLC List! Ragnarok Odyssey has plenty of DLC, I'll list the ones available on the JP PSN Store, and note if they're either free or paid.
Soundtrack: There are 12 DLC tracks available for download, and they're all free. The latest one was released 07/06.
Outfits: For download, only the Novice and Super-Novice outfits are available for download, and they're all free as well.
Treasure Chest: It seems to be a pack of a few items for the game, 4 items on the same DLC pack. It's also free, and there's only that one single chest.
Hats: Here's the best part of the DLC content, all sorts of hats available.
- Luxurious Crown; - Dokuro Hat; - Kafra Hat; - Kafra Hat 2 (the first one is standing, and this one is laid-down); - Apple of Archer; - Dropping Cat; - Bunny Ears; - Magestic Goat; - Poring Hat; - +4 Hats I don't recognize.
The ones in bold are paid, for 100 yens. The rest is free.
Dokuro Card: There seems to be a Dokuro Card that you can use in-game, and even though I can't read the description, it's for free as well.
Bottom-line: All DLC is free, with the exception of 4 hats.