Magic on the TL 3 battlefield

[Anthony]

Originally Posted by Fred Brackin

Thinking about it myself I'd use the guidance on Area Spells even though Pentagram isn't an Area Spell. It's at least a input on how other (mostly) Two-D spells work. So it's probably 12 feet up and probably not at all into the floor.

A number of area spells clearly apply under the surface and don't specifically say so, and pentagram does not work if it doesn't descend below the surface.