Concept Skill: Stone Wall

Stone Wall
Spell. If target foe is moving, that foe is struck for 20..40 earth damage and knocked down. If that foe was moving faster than normal, they are Dazed for 5..10 seconds.
Cost: 10 Cast: 3/4 Recharge: 20
Appearance: A stone wall suddenly rises up out of the ground in front of your foe, then sinks back down after a moment.

Basically, an anti-runner skill for Earth Magic, and an entertaining one to boot.
Made effective by the relatively fast casting speed and the lack of projectile, kept in check by the 10 Energy cost and the 20 second recharge, making it not as reusable as water trident. Also a way to daze people randomly.
(Maybe Shameful Fear + Stone Wall against a caster who is kiting?)

Opinions?

Quite nice, as a geomancer myself i can't say i'd use it because I've got a very solid build already.

Well balanced though

Lol, I'm picturing the skill in my mind right now

"Alright, almost at the flag sta- BOOM! My face!"

I think maybe it should get bumped up to 15e cost, it looks like a pretty potent skill.