If cast underwater, heat metal deals half damage and boils the surrounding water?

[eyebreaker7]

" If cast underwater, heat metal deals half damage and boils the surrounding water."
Is the boiling water what is dealing the damage? or is it still heat based? does P.F. Energy, Resist Energy, or P.F. Elements help at all?

[Hachristo]

According to the DMG, "Boiling water deals 1d6 points of scalding damage, unless the character is fully immersed, in which case it deals 10d6 points of damage per round of exposure." This is under the "Heat Dangers" section in "The Environment" section in the glossary. Since it is a heat danger, I'd say the damage is heat based. I believe this damage is in addition to the half damage from heat metal, which actually makes heat metal significantly better when the target is fully immersed. I'd say your protection spells would still protect you from this kind of heat.