Wondrous Item, very rare
If a creature takes damage from the arrow, the creature must make a DC 17 Strength saving throw, or yellow strips of magical energy loop around the creature. Its flying speed (if any) is reduced to 0 feet for 1 minute. An airborne creature affected by this arrow safely descends at 60 feet per round until it reaches the ground or the effect ends.
Once an arrow of earthbinding deals its damage to a creature, it becomes a nonmagical arrow.
Notes: Set: Speed (Flying), Control, Debuff, Combat, Bane