Web

2nd-level Conjuration Spell (Concentration)

Casting Time: 1 action
Range: 60 feet
Components: V, S, M (a bit of spiderweb)
Duration: 1 hour (concentration)

You conjure a mass of thick, sticky webbing at a point of your choice within range. The webs fill a 20-foot cube from that point for the duration. The webs are Rules#Difficult Terrain and lightly obscure their area.

If the webs aren't anchored between two solid masses (such as walls or trees) or layered across a floor, wall, or ceiling, the conjured web collapses on itself, and the spell ends at the start of your next turn. Webs layered over a flat surface have a depth of 5 feet.

Each creature that starts its turn in the webs or that enters them during its turn must make a Dexterity saving throw. On a failed save, the creature is Restrained as long as it remains in the webs or until it breaks free.

A creature Restrained by the webs can use its action to make a Strength check against your spell save DC. If it succeeds, it is no longer Restrained.

The webs are flammable. Any 5-foot cube of webs exposed to fire burns away in 1 round, dealing 2d4 fire damage to any creature that starts its turn in the fire.

Source: Player's Handbook (2014)