So, Molten Man. A psychic power from the Pyromancy Discipline in Tome of Fate.
One of the effects of it is:
"Before accounting for Toughness and Armour, the psyker reduces all Damage from heat and fire and half of the Damage caused by plasma, las, and melta weapons."
Does that make any sense to anyone? The Errata hasn't been updated since ever, so that's no help. Goddammit FFG, we all know your proof-reading is terrible, but must you also be terrible at publishing erratas?