@GunnerMcGrathDo the temp HP from Heroism accumulate each round, or are the same X HP just replenished each round if they were lost? Temporary hit points never accumulate, unless a spell, feature, or other effect says otherwise.

— Jeremy Crawford (@JeremyECrawford) January 6, 2015

@GunnerMcGrath“Gains temporary hit points at the start of each of its turns” sounds like temp HP total goes up each round if not lost. ? Nope. The spell would tell you to add the temporary hit points together if that was the intent.

— Jeremy Crawford (@JeremyECrawford) January 7, 2015