So I recently picked up an assassin pyro soldier and have been levelling him up with my carriage rider who is equipped with freezing talismans.
Now, the pyro's basic attack "Melt" states: "deals magic damage to a single target. Consumes burn effects on perfect attacks. The consume effect deals true damage and removes the effect."
After farming game of death a few times I noticed the following: when carriage rider freezes an enemy and the pyro solider then uses melt on that same target, it deals true damage and consumes the freeze effect, removing it completely.
I tested this a few times and it happens every time, even when there were no burn effects present.
*post has been clarified, see below*