Purpose
A Greater Celestial Entity is functionally like an Extramultiversal Entity as they nearly rival the power of one, the main differences are that a Greater Celestial Entity is not from beyond The Edge Wall, they can't leave the multiverse however they have access to anywhere inside the multiverse an Extramultiversal Entity could go.
Unlike Extramultiversal Entity, Greater Celestial Entity are usually kinder and more merciful.
Powers
Each Greater Celestial Entity has a variety of powerful cosmic abilities, all Greater Celestial Entity have varied power sets, going from slight variation to no similarity at all, all Greater Celestial Entity are Immortal to everything from inside the multiverse.
Appearance
Much like Bulk Beings and Extramultiversal Entity they can have any appearance however most Greater Celestial Entity rarely change how they look despite being able to do so.
Trivia
All Greater Celestial Entity are at least partially Immortal, and very powerful
The All-Watcher is the oldest and most powerful Greater Celestial Entity