Reforge

Reforging is a means of randomizing the additional mods to a base item. The Goblin Tinkerer charges money for this process, and it is applied once for free when an item that can have additional mods is encountered for the first time. This process generates stats that are broadly useful, such as movement speed or increased defense, for as long as the item is equipped. As the mods are randomized, it is possible to get stats on items that give up to 5 bonuses at once or with bad luck 3 stats are lowered up to 25%. The displayed amounts may vary depending on the item's base values, which are multiplied with a fixed value and then rounded. For example, the Murderous prefix on a Handgun will display a 7% damage increase, while a Magic Missile will display a 9% increase.

The process is expensive, and is probably intended as a "gold sink." If the item is crafted, one means of generating new mods is to rebuild the item; that may not be practical, hence the "Reforge" option on the Tinkerer. Currently, the Goblin Tinkerer charges the items sell value * 5 (reforged items are more expensive to reforge again due to their higher sell value).

Items can only be reforged if they have a sell value. If they have no sell value, like the Water Bolt, they cannot be reforged.

It should be noted that an item with mods can be used in the crafting of other items if it is marked as a material. Doing so does not preserve the mods; an Enchanted Boomerang's mods are lost when used to create a Flamarang, which will get new mods randomly assigned upon creation. Thus, if you have a weapon or accessory that already has useful mods, you may wish to consider finding another of the same to use in crafting.

There are 112 different reforge modifications in total at the moment.

Accessory Mods
Accessory mods are always "on" -- they are applied to the character no matter what they are wielding, as long as they are equipped. Every accessory item can be reforged with the exception of Guide Voodoo Doll and all Music Boxes. Accessories can have one of the following mods attached to them:

Weapon mods
These mods only apply when the weapon is being used. Weapons that have no Knockback cannot be reforged with mods that change Knockback, including, but not limited to, Drills, Magical Harp and others.

Universal
Flails, Spears, Boomerangs and Chainsaws can only have universal prefixes. Universal mods can also be found on all other weapon types.

Displayed values may differ due to rounding.

Common
All weapons that are either melee, ranged, or magical can have these mods. There is no weapon whose best mod is in this category, though these mods are not especially bad.

Displayed values may differ due to rounding.

Melee
All Pickaxes, Hammers, Hamaxe and Melee Weapons can be reforged with these mods, in addition to the top two categories. The best melee prefix is Legendary.

Displayed values may differ due to rounding.

Ranged
All Bows and Guns (Excluding the Space Gun and Laser Rifle which count as Magic Weapon) can be reforged with one of the following mods, in addition to the top two categories. The best ranged prefix is Unreal.

Displayed values may differ due to rounding.

Magic
All Magic Weapons (mana consuming) with the exception of the Water Bolt can be reforged with one of the following mods, in addition to the top two categories. The best magic prefix is Mythical.

Displayed values may differ due to rounding.

Complete List
Less the Attack Animation Speed the better. Less the Mana Cost the better.

These values are approximate and may vary slightly.