Drum of UpheavalEquipment 20
Source Pathfinder Lost Omens: The Grand Bazaar
Price 60,000 gp
Weight 1 bulk
This heavy drum is engraved along the sides with images of centaurs in fierce combat. The drum grants you a +3 item bonus on Performance checks you make using the drum. Additionally, it imparts the rhythms of two songs upon your mind as soon as you touch it. One is a fast marching cadence; the other is a frenetic ritual dance. Each song has a different activation.
Activate 
Interact
Frequency once per minute
Effect Dozens of spectral centaurs burst from the drum and stampede in a 60-foot cone. The stampede deals 7d10 force damage (DC 43 basic reflex).
Activate Interact
Frequency once per day
Effect The drum casts a DC 43 reflex Earthquake spell.
Craft Requirements You are a centaur.
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.
EarthEffects with the earth trait either manipulate or conjure earth. Those that manipulate earth have no effect in an area without earth. Creatures with this trait consist primarily of earth or have a magical connection to that element.
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.