If we are discussing that latest thread about hitboxes, one key difference between the idea and this mythic concept is the idea that a hitbox is "binary" in round terms. A hitbox can either be checked because enough damage was done, or remain unchecked (meaning the damage dealt does nothing). Further, a single hitbox can only be checked once per round, so if a monster has 3 hitboxes it cannot be killed faster than 3 rounds.Sorry: "hitbox" meaning "mythical trait" / "final boss" / once you kill it, it gets back up with a new set of HP and loses all conditions and recharges its stuff. I don't know if we have a standard word for that idea yet. I think I like "mythical trait" best so far.
Or the "hitbox" idea that Reynard had where each area of the monster has its own HP/condition/etc., and taking down each part makes it weaker.
Mythic does provide a fresh set of hitpoints after a nova attack (so can allow for nova damage to be wasted) and removes conditions, so its midway there, but its not quite a protecting as that full hitbox concept. You could argue that the hitbox idea is the more ideal in terms of truly ensuring a high level monster sticks around long enough to deliver threat...but its also a lot more gamist of a concept.