expand_less For now, we'll use the mythic rules unchanged.  Player characters won't be mythic by default, but they will earn this status in play.  More house rules will likely follow, but there are a few stylistic changes:
In the World of the Ledge, Legends, Immortals, and Avatars are mythic characters.  These are usually referred to as the Three Aspects.  Not all mythic characters belong to these Three Aspects, but all characters with at least one are mythic characters.  Dragons, for example, have their own mythic path not inherently connected to the Three Aspects.  It is generally believed that deities possess all Three Aspects and that a mortal that attains all three will become a god.
Legends possess a legendary style that inspires tales for the ages.  These characters naturally attract followers, gaining the Leadership feat for free and the ability to recruit cohorts and followers without spending additional character points (CP).  In addition, they may select mythic abilities from any mythic path that boosts their allies or matches their style.  When a legend dies, their cohort may take their place (gaining any levels or mythic tiers necessary to catch up to the rest of the party).  Each Legend's style should reflect a tight narrative theme.  Legends that adhere to this theme will be rewarded with boons to compensate (ask GM for details).
Immortals possess an immortal secret that prevents them from dying by any known method.  As soon as their immortal secret is discovered, they are vulnerable, and so most immortals go to great lengths to keep the secrets of their immortality hidden.  In practice, this means that immortal characters can never be permanently slain or removed from play (at most they would need to wait 24 hours in-game, as the base mythic ability).  In addition, they may select mythic abilities from any mythic path that protect them or prevent their death.  Mythic mortal characters don't have access to the Immortal base mythic ability unless they become immortal.
Avatars possess an avataric power passed down through their blood or stolen from others.  These powers give absolute control over a specific domain, similar to the domains or portfolios of true deities.  In practice, this allows avatars to overcome challenges normally impossible for all but the gods (such as the ability to cast spells in anti-magic fields, create new races of creatures, or even grant spells to true believers).  In addition, they may select mythic abilities from any mythic path that match their domain.  All avatars are mortal - when they die their powers pass to their next of kin.  However, if a particularly strong-willed individual kills an avatar, there is a chance that these powers will pass to them instead.  Because of the method by which avataric powers are passed, it is possible for avatars to have more mythic tiers than their level, but this can fluctuate for some time before they bring their powers under control.