Demonic hellscapes
PoV Diego
The sphere collapsed upon impact with the ground, releasing all the air that was trapped within and releasing a shockwave powerful enough to instantly kill all of the demons on the ground, sending all the blood away in giant waves and releasing large quantities of aura all over the place.
It was something I discovered while playing with the strings. To keep their shapes, they naturally form two really strong anchors, and by carefully placing the anchors next to each other, a solid can be formed with air trapped within. The bigger the solid, the higher the pressure is within the anchor, and the higher the pressure, the stronger the attack will be. However, moving such large volumes of air requires so much strength that it's currently only possible thanks to the soul weapon, which can freely increase its size and mass.