Lava Whip is a skill located in the Ardent Flame (which can be found in the Dragonknight skill tree). Lava Whip is a base skill, and can be morphed into Molten Whip or Flame Lash.
Lava Whip deals the following types of damage: Flame Damage. Which means that it gets buffed by the following blue champion point trees: Elemental Expert, Elf Born, Spell Erosion. Also the following red champion point trees protect against this skill: Elemental Defender.