Earthbind LodestoneLevel 18 Uncommon

When thrown to the ground, this smooth metallic stone hits with such force that it knocks airborne creatures from the sky.

Wondrous Item        85,000 gp

Power Daily (Standard Action)

Throw this stone to the ground in your square and make an attack: Close burst 5; affects creatures with a fly speed; +23 vs. Fortitude; on a hit, the target loses the ability to fly or hover until the start of its next turn. If a target is airborne when it is hit, it falls.

Published in Adventurer's Vault, page(s) 170.