Four Violet Flames Formation

= Four Violet Flames Formation =
==== Ninjutsu (Universal) ====
Level: 	B Rank (5)
Hand Seals: 	Snake → Claps hands
Casting Time:	Standard Action
Range: 	Varies
Area: 	1 Wall between two users
Duration: 	1 minute/level, Concentration
Saving Throw 	None
This is a solid, strong barrier formation, performed by four shinobi. Standing in a square formation, the performers are covered from all sides. The faces of the barrier are made from pure purple flames. The barrier does not allow anyone to enter or exit so long as the ninja are unharmed. The body of anyone touching it will immediately be engulfed in flames. In addition, there is no way to destroy the formation from inside the barrier, since the four people also have a barrier on the inside protecting them.
You cause a flat, vertical iron wall to spring into being. The wall inserts itself into any surrounding nonliving material if its area is sufficient to do so. The wall cannot be conjured so that it occupies the same space as a creature or another object. It must always be a flat plane, and the four corners always meet together at right angles. This construct also comes with a top, so flying is not an option, but no floor. 
A section of wall has 30 hp per 4 caster levels of the highest level between the two adjacent corners that make a single side of the formation (not across diagonals, following the perimeter). Each 5-foot section of wall has shares hitpoints and hardness 10. 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 25 + 2 per four caster levels of both casters. Any melee attacks against the barrier cause the attacker to take 1d6 points of fire damage per caster level of each person on the two ends of the wall that is being attacked.