Barricade Stone (Cube)Consumable 8
Source Pathfinder #171: Hurricane's Howl
Price 80 gp
Weight negligible
Activate 
command, Interact
The ancient inhabitants of Bloodsalt crafted these magic rocks to construct defenses quickly. In its stone form, a barricade stone appears to be a simple pebble with an unnaturally geometric shape. The size and shape of the stone's final form depends on the type of barricade stone.
When you activate the barricade stone, you drop it on the ground, throw it up to 20 feet away, or sling it using a sling weapon.
Upon landing, the stone instantly and permanently expands. The stone grows to its maximum size. While normally items with the structure trait put creatures in their area inside the structure, this effect creates solid stone, so it can't be placed in an area where there are creatures. While it's likely to take some time even with the right tools, an activated barricade stone can be destroyed the same as any normal stone structure (Hardness 14, HP 56).
Type: Cube
This seemingly simple six-sided die was designed to block a corridor. When activated, it grows to fill a solid square or rectangular space no more than 20 feet on any side. The cube fills spaces well enough that Tiny creatures can't slip through, but it's far from a perfect seal. Liquids, gases, and minuscule creatures such as insects can still find ways around it. Depending on the irregularities of the space the cube fills, it might be possible to see or hear past it.
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.
ConjurationEffects and magic items with this trait are associated with the conjuration school of magic, typically involving summoning, creation, teleportation, or moving things from place to place.
ConsumableAn item with this trait can be used only once. Unless stated otherwise, it's destroyed after activation. Consumable items include alchemical items and magical consumables such as scrolls and talismans. When a character creates consumable items, they can make them in batches of four.
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.
StructureAn item with the structure trait creates a magical building or other structure when activated. The item must be activated on a plot of land free of other structures. The structure adapts to the natural terrain, adopting the structural requirements for being built there. The structure adjusts around small features such as ponds or spires of rock, but it can't be created on water or other nonsolid surfaces. If activated on snow, sand dunes, or other soft surfaces with a solid surface underneath, the structure's foundation (if any) reaches the solid ground. If an item with this trait is activated on a solid but unstable surface, such as a swamp or an area plagued by tremors, roll a @Check[type:flat|dc:3] each day; on a failure, the structure begins to sink or collapse. The structure doesn't harm creatures within the area when it appears, and it can't be created within a crowd or in a densely populated area. Any creature inadvertently caught inside the structure when the item is activated ends up unharmed inside the complete structure and always has a clear path of escape. A creature inside the structure when the activation ends isn't harmed, and it lands harmlessly on the ground if it was on an upper level of the structure.