The plates and joints of your opponent's armor become as rigid as stone, encumbering his movement.

You cause the target's armor to swell and stiffen, slowing the wearer's movement and trapping him within.

The target's land speed is reduced to 10 feet.

If the target has a burrow, climb, or swim speed, these are also reduced to 10 feet.

The target also loses any Dexterity bonus to AC for the duration of the spell.

While affected by this spell, the target cannot remove his armor; its joints are too tight and restrictive to escape from.

This spell has no effect on unarmored opponents, creatures with only natural armor or an AC bonus from items other than armor, or those using only shields.