Very interesting concept for a spell, initially the level seemed a bit high but to combine a banishment and summoning spell into one it seems appropriate.
Level: Sorc/Wiz 9
Components: V, S, M, XP (see text)
Casting Time: 1 standard action
Target: One creature
Duration: 1 round or more; see text
Saving Throw: Fort negates
Spell Resistance: Yes
The target of this spell loses the powerful body they previously possessed only to have it replaced by an origami construction of identical make. The creature loses all armor, shield, and natural armor bonuses to AC, any extraordinary damage reduction, and any permanent immunity or resistance to fire. Its Strength score becomes one, but it gains the ability to glide by jumping straight up; it can then travel sideways 10ft for every 5ft it is to fall. Critically, the target of this spell also becomes especially vulnerable to fire, taking double damage from all such sources.
XP Cost: This spell's effect lasts for 1 round, plus an additional round for every 100XP spent on its casting, up to a maximum of 1000XP.
Material Focus: A well-crafted origami crane (costing at least 1gp)
Next Challenge: A spell that produces some kind of unusual/exotic weather phenomenon.