If you thought the Crystarium system was complex, check out how you'll upgrade your weapons in FFXIII.
Final Fantasy XIII's Crystarium system looks like it will offer hours and hours of customization. It's not alone, though. In addition to customizing your characters through the Crystarium system, you'll also be able to customize your weapons using a separate system.
Weekly Shonen Jump offered first details on the weapon customization system a couple of weeks back. Famitsu has returned with the specifics.
FFXIII's weapon customization system is know by just the Japanese word for "reform" (all out of wacky system names, Japan?). This system allows you to power up your weapons and accessories by feeding them special materials that you collect during the game.
The magazine states that once you've advanced far enough in the story, you'll be able to visit particular places in order to conduct the weapon and accessory modifications. This seems to imply that you won't have access to the reform system at all times, although the modification screens shown in the magazine do look like they're part of the main menu.
To use the system, you first select the weapon or accessory that you want to upgrade. You're then presented with a list of materials that you can feed to the item. You can select the material that you want to give, and its quantity.
Adding materials to a weapon can have different effects depending on the material in question. Some materials will increase the weapon's experience value, leading to level-ups and eventual form changes (detailed below). As an example, making use of a Liquid Crystal Lens item gives Lightning's Blaze Edge sword 100 experience points. The management screen lists how much experience you need to make the sword rise to the next level. If you need 300 experience points, and you happen to have three Liquid Crystal Lens items, an easy way to to get a quick level up is to hand over the three items.
Other materials have special effects. Famitsu mentions one example, a material that makes it so that the next material that's added to the weapon has a 1.25 multiplier for its awarded experience. Use this material first, and the next Liquid Crystal Lens item would give you 125 experience points rather than 100. Some items have the reverse effect, reducing the experience of subsequent items.
Levelling up a weapon increases its capabilities and also gives it special abilities. Progress through enough level-ups, and the weapon will eventually reach its limit. Its level status will display a star. This indicates that you can make the weapon change form. To actually make the weapon change form, you have to first obtain a special material for it.
There may be a good reason why the transformations aren't automatic. When you transform a weapon, it actually ends up being weaker than its fully maxed out predecessor. Of course, by building up the new weapon with materials, you'll eventually result in an even more powerful weapon.
Jump detailed a couple of weapon transformations in its previous article. Transforming a weapon gives it a new physical appearance. Lightning's default Blaze Edge changes into Slash Carbon. Like Blaze Edge, Slash Carbon is a combination gun and sword.
Vanille's initial weapon is the horribly painful-looking Bind Rod. Its head piece looks like a pair of antlers. Its body consists of four long wires with hooks that deal damage to enemies by latching on and pulling (eek!). Transform Vanille's weapon, and the head piece will change to something that looks like feathers rather than antlers. The body is still wires and hooks, though.
Snow uses his bare hands to fight, but his weapon is actually his coat. When running about outside of battle, the coat displays no unique logos. But get into battle, and patterns appear on its back and sleeves. The initial pattern is "Wild Bear." It shows the face of a bear on the back and sleeves. Upgrade the coat, and the patterns change. Famitsu provides a look at one additional pattern which, compared to the Wild Bear coat, looks like it could have increased magic power.
The common theme in all of the above is that while the weapons transform, they don't completely change to a different class of weapons. Your characters are stuck using their default weapon class. The game has a total of six party members: Lightning, Sazh, Snow, Hope, Vanille, and Fang. Their weapon types are, respectively, transformable sword, gun, coat, boomerang, rod, and lance.
There are a number of ways to obtain the special materials required to use the weapon upgrade system. You'll find over 100 material types in all. Some can be found in treasure boxes, some are earned by winning a battle, some can be purchased in shops. The magazine speculates that you can also earn special materials as rewards for clearing missions. It's also likely that you'll be able to use a steal move in battle to steal materials from your foes.
You can also get materials by selecting to destroy one of your current weapons or accessories. You lose the weapon, but you get materials in return, some of which may be rare.
With the weapon reform system, FFXIII looks like it will be changing some of the paradigms we've come to expect from Japanese RPGs. The idea of buying a weapon in a shop seems to be de-emphasized. Director Motomu Toriyama, in a short interview with the magazine, notes that, although you can buy weapons in a shop, they start off at base level -- not in a particularly strong form.
In FFXIII, explained Toriyama, it's possible to fight the last boss with the very first weapon that you obtained in the game. This assumes, of course, that you've kept on building it up throughout the adventure. Your characters are capable of keeping multiple weapons in their possession, so there will be room for experimentation.
With all the customization options offered by the Crystarium system and now the weapon reform system, FFXIII looks positioned to cause a boom in the strategy guide business. At the very least, that FFXIII Ultimania Guide should end up being thicker than a phone book.
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I REALLY want FF13 now so I can try all of this 
