Thunderhead Bident

Level 1: Any weapon ability that deals rolled damage using this weapon deals an extra 1 sonic damage. Additionally, when the weapon is used with any ability that pushes a target, you gain a +1 bonus to the forced movement distance. If the weapon is used with a damage-dealing ability that doesn't impose forced movement, you can push the target 1 square.

Level 5: The weapon's extra sonic damage increases to 2, and the additional distance or distance of a push for abilities using the weapon increases to 2 squares. Additionally, the weapon can be used with ranged weapon abilities, and gains power the farther it is hurled. For each 2 squares the weapon travels to the target of a ranged strike, the strike deals an extra 1 sonic damage.

Level 9: The weapon's extra sonic damage increases to 3, and it deals an extra 1 sonic damage for each square it travels as part of a ranged strike. Additionally, whenever you make a weapon strike using this weapon, each enemy adjacent to the target takes 6 sonic damage.