Firewalk 2014

The creature you cast firewalk on becomes immune to fire damage. In addition, that creature can walk along any burning surface, such as a burning wall or burning oil spread on water, as if it were solid and horizontal. Even if there is no other surface to walk on, the creature can walk along the tops of the flames.

When you cast this spell using a spell slot of 7th level or higher, two additional creatures can be affected for each slot level above 6th.