or use a ward. thier area seems a bit larger to me. and they definitly extend upwards CRAZYly^^ tested this on a dvergr tower which had a really high mistlands rock above it. even on the top of this rockpillar the ward was blocking me despite showing the sphere ending way below me. it looks like a sphere but believe me : the actual effect isnt a sphere. definitly not. more like a tube that stands on its flat side. thats how it works. it blocks all air spawns above it. a sphere couldnt do that in the first place.