Earth Release: Rock Shelter

= Earth Release: Rock Shelter =
==== Ninjutsu (Earth Release) ====
Level: 	C (3)
Hand Seals: 	Tiger → Dog → Snake → Hare
Casting Time:	Standard Action
Range: 	Close (25 ft + 5 ft every two caster level)
Area: 	20 ft radius sphere
Duration: 	Permanent
Saving Throw 	None
The user surrounds themselves with earth, taken from the immediate vicinity and creates a formation of rock that is capable of protecting the user. Doing so, seemingly leaves the surrounding terrain unaltered, even when the quantity of earth used is enough to form a complete dome around multiple individuals. The user can also manipulate the resulting shelter to have openings in it to be able to observe outside. 
You cover yourself and any adjacent allies in an earth dome, 1 inch thick per four caster levels. Each half of the sphere has your caster level's worth of hit points per inch of thickness. A section of wall whose hit points drop to 0 is breached. If a creature tries to break through the wall with a single attack, the DC for the Strength check is 20 + 2 per inch of thickness. People inside the sphere have total cover against incoming attacks, though they still have line of sight.