Web creates a many-layered mass of strong, sticky strands. These strands trap those caught in them. The strands are similar to spiderwebs but far larger and tougher. These masses must be anchored to two or more solid and diametrically opposed points or else the web collapses upon itself and disappears. Creatures caught within a web become grappled by the sticky fibers. Attacking a creature in a web doesn't cause you to become grappled.
Anyone in the effect's area when the spell is cast must make a Reflex save. If this save succeeds, the creature is inside the web but is otherwise unaffected. If the save fails, the creature gains the grappled condition, but can break free by making a combat maneuver check or Escape Artist check as a standard action against the DC of this spell. The entire area of the web is considered difficult terrain. Anyone moving through the webs must make a combat maneuver check or Escape Artist check as part of their move action, with a DC equal to the spell's DC. Creatures that fail lose their movement and become grappled in the first square of webbing that they enter.
If you have at least 5 feet of web between you and an opponent, it provides cover. If you have at least 20 feet of web between you, it provides total cover.
The strands of a web spell are flammable. A flaming weapon can slash them away as easily as a hand brushes away cobwebs. Any fire can set the webs alight and burn away one 5-foot square in 1 round. All creatures within flaming webs take 2d4 points of fire damage from the flames.
Web can be made permanent with a permanency spell. A permanent web that is damaged (but not destroyed) regrows in 10 minutes.