Unlike most other elemental reactions, this reaction increases the damage of the Hydro or Pyro attack that triggers the reaction. In addition, changing the order in which elements are applied will result in slightly different effects; specifically, there are different damage multipliers depending on whether a Hydro or a Pyro attack triggers the reaction.
Vaporize damage is influenced by ATK, Elemental Mastery, and all other multipliers considered in standard damage calculation. The order of elemental application affects the damage multiplier: if the triggering element (the second element applied) is Pyro, the multiplier is 1.5; if the triggering element is Hydro, the multiplier is 2. See Damage for more details.
When Pyro meets Hydro, Vaporize occurs. Vaporize causes the triggering source of Hydro or Pyro DMG to receive a certain DMG Bonus. If the triggering DMG type is Hydro, it will receive a greater DMG Bonus than Pyro.