The axiomatic fusion imbues a weapon with divine energy from a lawful deity. Any attacks with the weapon are lawful-aligned. Damage from the weapon bypasses DR/lawful and ignores the energy resistance of chaotic dragons and chaotic outsiders. The axiomatic fusion can’t be added to weapons that have the anarchic fusion.

The corrosive fusion weaves the destructive power of acid into the weapon’s form. Half the weapon’s damage type is replaced with acid damage. You can activate or deactivate the corrosive fusion as a swift action. If the weapon already deals two types of damage, replace one of them with acid (you decide which damage type is replaced each time you activate the corrosive fusion). You can add this fusion only to a weapon that does not already deal acid damage. This fusion never causes a weapon that normally targets KAC to target EAC.

The anarchic fusion imbues a weapon with divine energy from a chaotic deity. Any attacks with the weapon are chaotic-aligned. Damage from the weapon bypasses DR/chaotic and ignores the energy resistance of lawful dragons and lawful outsiders. The anarchic fusion can’t be added to weapons that have the axiomatic fusion.

You can apply the devastating fusion only to a weapon with two or more critical hit effects. When you score a critical hit with a weapon that has the devastating fusion, you can select two of the critical hit effects to apply to the target (even if you are normally required to select just one critical hit effect).

The flaming fusion imbues a weapon with the fiery power of a star. Half the weapon’s damage type is replaced with fire damage. You can activate or deactivate the flaming fusion as a swift action. If the weapon already deals two types of damage, replace one of them with fire (you decide which damage type to replace each time you activate the flaming fusion). You can add this fusion only to a weapon that does not already deal fire damage. This fusion never causes a weapon that normally targets KAC to target EAC.

A weapon with the hybridized fusion replaces much of its technological functions with magic counterparts. It gains the analog weapon special property (see page 180), and the core function of the weapon is considered to be a hybrid of magic and technology (rather than only the fusion counting as a hybrid item). A hybridized weapon still consumes ammunition and battery charges normally.

A weapon with the venomous fusion gains the injection weapon special property (see page 181). Only a single attack each day may benefit from this property, and you must announce before making an attack that it is an injection attack. Regardless of how many targets you can hit with a single attack from your weapon, only a single target of your choice is exposed to the drug, medicinal, or poison when you use the injection property in an attack. Only weapons that deal piercing or slashing damage can benefit from this fusion.

A weapon with the merciful fusion often hums pleasantly when at rest and makes soft, airy musical noises when it is used to make an attack. The magic of this fusion subdues the damaging effect of the weapon it is added to. While this fusion is active, the weapon’s regular damage becomes nonlethal damage. If the weapon deals two types of damage, both of the damage types become nonlethal. You can activate or deactivate the merciful fusion as a swift action.

A weapon with the spellthrower fusion is able to have a single spell gem loaded into it at a time. It takes 1 minute to load a spell gem, and only gems containing a spell with a casting time of one standard action or less and a spell level no greater than one-quarter the weapon’s item level can be loaded into the weapon.

If you are proficient with and wielding the weapon, as a full action you can cast the spell contained within the spell gem rather than make a normal attack. This allows you to use the spell gem as if you were a spellcaster with the spell on your class’s spell list.

Unlike the normal rules for using a spell gem, it does not matter if the gem’s item level is higher than your caster level (even if your caster level is 0). However, if the spell gem’s item level is higher than your base attack bonus, once you’ve spent the full action to cast the spell, you must succeed at an attack roll with the weapon against an AC equal to the spell gem’s level + 1 or you fail to cast the spell. This roll represents your expertise with the weapon, and no actual attack or ammunition is used. If you fail to cast a spell from a spell gem, the spell is expended harmlessly and the spell gem is destroyed.

With the vorpal fusion, a weapon can tear between the molecules of a creature. The weapon gains the severe wound critical hit effect (see page 182). If the weapon already has a critical hit effect, when you score a critical hit, you can apply either the weapon’s normal critical hit effect or the severe wound effect. Only a weapon that deals bludgeoning, piercing, or slashing damage can benefit from this fusion.