The second section, as the whole is apparently too long to post.

II. What You Can Fuse:

The nitty-gritty, the fine details: a basic breakdown of what will be in the Item Fusion section, as well as what else you can fuse.

1. Elemental Crystals:

The most common type of Fusion Item. Exactly what it's called: crystals that'll add elemental effects to your items. There are four grades, each successively more powerful:

Elemental Shards: The weakest kind, and so the cheapest. These add status-related effects. For instance, a Fire Shard will add a burn chance to a weapon, or burn protection to armor. This bonus stacks with bonuses already present in your moves: the standard attack has a 5% chance of your element's status effect, and all bonuses on your weapon add onto that (e.g. an additional 10% burn chance on your weapon gives a Toa of Fire a 15% chance of burning with a standard attack; a 10% freeze chance will give a standard attack 5% chance of burning and 10% chance of freezing). Obviously, this makes using status effects more viable. Weak, but certainly effective.

Elemental Stones: The next grade up, and a bit more useful. Stones add stat bonuses: every element has two stats associated with them (Fire with HP and Offense, Air with Offense and Speed, etc.) and each stone will randomly add a +1 bonus to one of the two stats. Obviously, this is a great way to easily boost your stats outside of fighting enemies, especially at higher ranks where NPCs are unlikely to die in one hit (i.e. Nektann). Of course, this usefulness is offset by the relatively higher cost.

Elemental Gems: Much stronger than Elemental Stones, Gems actually add a chance for a move to your Item. Weapons get offensive moves, while armors gain useful support moves. Unlike Shards or Stones which essentially limit themselves to basic varieties like Fire and Ice, there is much greater availability in Gems. They come in a series: Fire has a Fire Gem, Blazing Gem, and Inferno Gem right off the bat. What separates these varieties (besides price) is that they each add a more powerful move into the item. Fire Gem essentially grants a fire element standard attack to a weapon, Blazing Gem adds a two-hit combo, and Inferno Gem a three-hit combo. Adding the next Gem in the series (e.g. Freezing Gem to a weapon with an Ice Gem already fused) removes the old move however, in favor of the new one. Keep that in mind.

Elemental Crystals: The last and strongest grade, full Crystals are essentially a Shard, Stone, and Gem combined into one, except even better. They have a higher status chance, add both stat boosts instead of just a random one, and a more powerful move built in. And they come in a variety, just like Gems (although the differences in a series are minor, aside from the added move). Obviously, there's a catch: they are prohibitively expensive (the basic Fire Crystal is 10,000 Widgets) and you can only add one to any item. So what's the benefit? They stack onto previous bonuses from Shards, Stones, and Gems. Stuck at 80% burn chance? A Fire Crystal adds 20% to that, making it a guaranteed burn. Only a 60% chance of activating your weapon's move? A Crystal will raise it to 75%. One other bonus will be explained in the Mechanics section: full Crystals have no net cap.

2. Boosts:

This is a much more limited category, but still highly useful. Boosts are fairly simple; the already implemented Item Boost being the prime example.

Item Boost (+, ++, +++, MAX): As you can see from the name, Item Boost comes in a series. First, Item Boost, then Item Boost+, Item Boost++, etc. Although not as directly obvious as the crystals, Item Boosts have a much more immediate impact: they raise the damage range or damage block of a weapon or armor. Simply, each successive boost raises it further, as you can only buy one of each for an individual item. So you can only buy one Item Boost for your starter Fire Sword, then one Item Boost+, and so on. Of course, if you sell that sword for a Fire Lance, then you can buy a new Item Boost for the Lance. Item Boosts are also notable in that adding one changes the name of your item (which also shows what's been added to it already). A basic Ice Lance with an Item Boost would become a Freezing Lance for instance, and you could no longer add an Item Boost to it; you'd need an Item Boost+ next.

For now, there are no other kinds of boosts, but their sheer simplicity makes them highly appealing.

3. Other Material:

Beyond crystals and boosts, there are other types of Fusion Materials that don't fit so cleanly into those previous categories. Essentially, the rest of the materials tend to be far more unique, with individual effects named in their description. You should have a basic idea of what a Fire Stone or Item Boost+ would do, but what about a Protosteel Bar? Basically, this is the miscellany of Item Fusion; whatever's left over that I feel like adding.

4. Artifacts:

Artifacts are similar to Other Materials; however, Artifacts do have a use outside of Item Fusion, offering stat bonuses and the like. Of course, this dual purpose means they are much rarer, typically being drops from NPCs instead of store-bought. Artifacts are weird; they may simply transfer their effects to the item, or maybe amplify the effects already present. It's up to you if you feel like taking a risk.

5. Other Items:

Say you've taken your starter sword, and been adding upgrades to it for a while, fusing Shards, Stones, Gems, even a Crystal or a Golden Amulet or an Item Boost++ into it. But sadly, it's no longer up to par; it simply can't deal enough damage to that Makuta NPC. But what do you do? Do you sell it for far less its actual value?

Of course not. You can fuse your old upgraded Inferno Sword to your fancy new Energized Flame Saber, and simply transfer its bonuses: problem solved. This is the only kind of fusion that requires you to pay: you need to buy an Item Forge for 500 Widgets. Other than that, the process is simple as always.