"You can create military structures with your earth magic? While in battle?" Sirius thought that this was something that could only be done by master earth mages. The idea that Walker could spontaneously create some form of wall or tower would mean that he could create a war front line in a battle to hold ground.
"Well it takes a lot of mana and time so I need someone to defend me while I get it ready. My imagination is key though. I use the ideas of structures around me then imagine them forming out of the earth with my high earth sculpting skill. Then I have them start to form underground. After that I make it rise. It works pretty well." Walker was letting himself brag just a little since no one seemed to talk about this use of his earth magic.
"That sounds like it should be a focus in a battle. You could push the border walls and hold them in the blink of an eye." Sirius was already seeing this as a permanent structure which Walker was sure to fix.
