As a GM, I have a problem with the related issue of Mythic Damage and Mythic DR. Mythic tiers are not necessarily epic as per the old ELH definition, it is understood. But it leads to an interesting issue: a 20th level character with a standard PC class is not able to deliver mythic damage without an epic weapon, whereas a 10th level character with 5 Mythic tiers can. It seems quite odd because the standard 20th level character is already "epic" in a way, isn't he ?