Wall of Force is truly excellent, in my opinion. Summon Monster V is as good as the others are at their respective levels. Very nice.
And how about this one?
Corporeal Instability
Transmutation [Wild]
Level: Drd 4, Sor/Wiz 5
Components: V, S, M
Casting Time: 1 action
Range: Medium (100 ft. + 10 ft./level)
Target: One creature
Duration: 1 minute/level
Saving Throw: Fortitude negates (and see text)
Spell Resistance: Yes
Corporeal instability causes the target’s body to destabilize into an amorphous, ever-shifting mass. Unless it controls itself by asserting its sense of self, the creature’s body melts, flows, writhes, and boils.
The affected creature is unable to hold or use any item. Clothing, armor, rings, helmets, and backpacks become useless. Large items—armor, backpacks, even shirts—hamper more than help, reducing the creature’s Dexterity score by 4. Soft or misshapen feet and legs reduce speed to 10 feet or one-quarter normal, whichever is less. Searing pain courses along the nerves, so strong that the creature cannot act coherently. It cannot cast spells or use magic items, and it attacks blindly, unable to distinguish friend from foe (-4 penalty to hit and a 50% miss chance, regardless of the attack roll). At the end of the spell’s duration, the creature returns to its normal form.
Each round the creature spends in an amorphous state deals 1 point of temporary Wisdom damage from mental shock. If the creature’s Wisdom score falls to 0, it loses all sense of self and becomes a truly shapeless mass unable to take any action for the rest of the spell’s duration.
A creature with a strong sense of self can regain its own shape by taking a standard action to attempt a Charisma check (DC 15). A success reestablishes the creature’s normal form for 1 minute. On a failure, the creature can still repeat the check each round until successful.
Corporeal instability is not a disease or a curse and so is hard to remove. A polymorph other or stoneskin spell cures the afflicted creature, as does a heal, restoration, or greater restoration. A separate restoration is necessary to restore any lost Wisdom.
Material Component: A caterpillar plucked, half-metamorphosed, out of its cocoon.