The illuminating fusion causes a weapon to gain the bright weapon special property (see page 181). You can deactivate this fusion as a move action, in which case the weapon acts as if it does not have the bright property until it is reactivated (which also requires a move action).

With the knockdown fusion, a weapon disrupts a target’s center of gravity. The weapon gains the knockdown 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 knockdown effect. Only weapons that deal bludgeoning damage can benefit from this fusion.

A weapon with the ominous fusion trails a shadowy haze behind it and moans a menacing dirge in battle. The weapon gains intimidation as a critical hit effect. 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 intimidation effect. A target affected by the intimidation critical hit effect is shaken for 1d4 rounds (Fortitude save negates). A creature that gains the shaken condition from a weapon with the ominous fusion can’t gain that condition again from the same weapon for 24 hours.

You can add this fusion only to a weapon that has the thrown weapon special property. A returning weapon flies through the air back to you after you make a thrown ranged attack with it. It returns to you just before your next turn (and is therefore ready to use again in that turn). Catching the weapon when it comes back takes no action. If you can’t catch it, or if you have moved since throwing it, the weapon drops to the ground in the square from which you threw it.

The seeking fusion causes an attack from a weapon to veer toward its target. This negates any miss chance caused by the target having concealment, though it has no effect on miss chances from other sources (and does not offset the miss chance from a target having total concealment).

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

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

A weapon with the trailblazer fusion manages to alter the nature of its attacks to overcome the penalties of some natural environmental effects. Its attacks ignore the cover provided by bogs and the cover creatures submerged at least chest deep in water receive from attacks made from the surface. Fire damage dealt by the weapon to underwater targets does half normal damage (rather than the normal one-quarter), and other attacks made underwater deal full damage (rather than the normal half damage).
Additionally, ranged attack rolls with the weapon don’t take a penalty due to the effects of storms, strong and severe winds, or windstorms. It can even be used to make ranged attacks in severe storms as if they were typical storms and in hurricane- force winds as if they were strong winds.

See Biomes on page 396 for more information on environments that impose attack penalties, and see Underwater Combat on page 405 for rules on attacking submerged targets.

The unholy fusion imbues a weapon with divine energy from an evil deity. Any attacks with the fused weapon are evil-aligned. Damage from the weapon overcomes DR/evil and ignores the energy resistance of good dragons and good outsiders. The unholy fusion can’t be added to weapons that have the holy fusion.

A weapon with the anchoring fusion has a chance to immobilize its targets. The weapon gains immobilization as a critical hit effect. If the weapon already has a critical hit effect, choose each time whether to apply the weapon’s normal critical hit effect or the immobilization effect. A target affected by the immobilization critical hit effect is unable to move from its space under its own power for 1d4 rounds. It cannot use any form of movement, including teleportation effects, to change its position. If the target is entirely contained in a mobile object (such as a starship or large vehicle), the target is immobile relative to its location within that object. Other creatures and forces can move the target normally.