Metal Melt

You uncork the vial and pour out its contents, and the armor you designate begins to soften and flow.

(Spell Compendium, p. 140)  
Originally posted on D&D tools

Transmutation [Fire]

Level: Sorcerer, Wizard 4,
Components: V, S, M,
Range: Close (25 ft. + 5 ft./2 levels)
Target: Metal object weighing up to 5 lb./level
Duration: 1 round
Saving Throw: Will negates (object)
Spell Resistance: Yes (object)

You alter the physical properties of a metal object so that it runs like water. The melted metal does not change temperature but flows as a liquid for 1 round and then returns to its normal solid state, usually in a form resembling a puddle. An item in a creature’s possession is allowed a Will save, using the creature’s saving throw bonus unless its own is higher.

Material Component: A drop of mercury in a vial.