Izroth executed his Third Sword Form: Collapsing Thunder with his Tempest Strikes still active. In turn, this caused the wind element from his Tempest Strikes to fuse with the lightning element from his sword form and created the storm element.
〈Battle Alert: Player Izroth has performed an Element Fusion of the wind and lightning elements to form the storm element!〉
As the blade of wind shot out towards Zephyr and carried along with it a powerful source of lightning, the two elements bent and morphed mid-flight as they fused into a single element. This changed the blade of wind with lightning attributes into a blade of the storm!
When the bolt of lightning crashed down, the blade of storm collided with it to form a typhoon around Zephyr.