Anchor SpearWeapon 13
Source Pathfinder #155: Lord of the Black Sands
Damage 1d6 Piercing
Type Simple
Price 2,800 gp
Weight 1 bulk
The tip of this +2 greater striking spear is large and wickedly barbed, and the haft is inlaid with fine silver lines that run the length of the weapon. Wielded by specially trained xulgath cavalry, anchor spears are used to prevent the escape of gogiteths or other monsters capable of climbing or burrowing.
Activate 
command
Effect The anchor spear extends into a +2 greater striking longspear or back to its original form as a +2 greater striking spear.
Activate 
command
Frequency once per 10 minutes
Trigger You damage a creature using the anchor spear
Effect The spear embeds itself into the creature, and the spear's haft splits along the silver lines to become a series of hooks attached to a thin but strong cable. As long as the anchor spear remains embedded in the creature, any time the creature burrows or climbs, it treats normal terrain as difficult terrain and difficult terrain as greater difficult terrain. The creature can spend an Interact action to attempt a DC 32 athletics check to remove the spearhead.
Critical Success The anchor spear is removed, becomes broken, and falls to the ground in the creature's space.
Success The anchor spear is removed, the creature takes 1d8 piercing damage, and the spear falls to the ground in a random space adjacent to the creature.
Failure The anchor spear remains in place, and the creature takes 1d8 piercing damage.
Critical Failure As failure, except the creature takes 2d8 piercing damage.
Traits
Something of uncommon rarity requires special training or comes from a particular culture or part of the world. Some character choices give access to uncommon options, and the GM can choose to allow access for anyone. Less is known about uncommon creatures than common creatures. They typically can't be summoned. The DC of Recall Knowledge checks related to these creature is increased by 2.
MagicalSomething with the magical trait is imbued with magical energies not tied to a specific tradition of magic. A magical item radiates a magic aura infused with its dominant school of magic. Some items or effects are closely tied to a particular tradition of magic. In these cases, the item has the arcane, divine, occult, or primal trait instead of the magical trait. Any of these traits indicate that the item is magical.
ThrownYou can throw this weapon as a ranged attack. A thrown weapon adds your Strength modifier to damage just like a melee weapon does. When this trait appears on a melee weapon, it also includes the range increment.
TransmutationEffects and magic items with this trait are associated with the transmutation school of magic, typically changing something's form.