Binding Snow

(Frostburn, DnD 3.5)

Transmutation[Cold]

Level: ; Cleric 3; Druid 3; Paladin 3; Ranger 3; Disciple of Thrym 3
Components: V, S,
Casting Time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Area: One 10-ft. square/level
Duration: 1 hour/level (D)
Saving Throw: Reflex negates
Spell Resistance: Yes

This spell must be cast on a snow field.
That snow field instantly freezes, impeding movement through the area.
A creature caught within the area can move only at half its normal speed.
By making a DC 20 Strength check or a DC 25 Escape Artist check, the creature can move at its normal speed for that round.
A creature that succeeds on a Reflex save is not impeded.