A web spell creates a many-layered mass of strong, sticky strands similar to spider webs but far larger and tougher. These masses must be anchored to two or more solid and diametrically opposed points - floor and ceiling, opposite walls, etc., or the web collapses upon itself and disappears.
The web spell covers a maximum area of eight 10' x 10' x 10' cubes and the webs must be at least 10 feet thick, so a mass 40 feet high, 20 feet wide, and 10 feet deep may be cast. Creatures caught within webs, or simply touching them, become stuck among the gluey fibers.
Anyone in the area when the spell is cast must roll a saving throw vs. spell with a -2 penalty. If the saving throw is successful, two things may have occurred. If the creature has room to escape the area, then it is assumed to have jumped free. If there is no room to escape, then the webs are only half strength. Creatures with less than 13 Strength (7 if the webs are half strength) are stuck until freed by another or until the spell wears off. Missile fire is generally ineffective against creatures trapped in webs.
Creatures with Strengths between 13 and 17 can break through 1 foot of webs per round. Creatures with 18 or greater Strength can break through 2 feet of webs per round. If the webs are at half strength, these rates are doubled. (Great mass equates to great strength in this case, and creatures of large mass hardly notice webs.) Strong and huge creatures can break through 10 feet of webs per round.
Furthermore, the strands of a web spell are flammable. A magical flaming sword can slash them away as easily as a hand brushes away cobwebs. Any fire - torch, flaming oil, flaming sword, etc. - can set them alight and burn them away in a single round. All creatures within flaming webs suffer 2d4 points of damage from the flames, but those free of the strands are not harmed.
The material component of this spell is a bit of spider web.