An enormous field of Lava can be found at the center of Dominus Tlacolotl in Stygia, surrounding the only Ebony Tower in that blasted plane. You should bathe in it. It deals 8 fire damage to any characters passing through the tile that are not Demons nor flying. Planar Protection provides no defense against this damage, but skills and items that provide Soak or immunity to fire damage may reduce or negate it. Lava costs two Action Points to move through, but can be flown over with no movement penalty.
No items can be found in locations filled with Lava.