Pathfinder Adventurer's Guild
At this point your character is capable of feats of vast destruction, creation, or rejuvenation. Throwing buildings, reviving the dead, creating new worlds, reviving the dead, all of these are possible to characters at this level given the right tools. At this point the gameplay comes down to exploiting weaknesses and acting first, going to blow for blow really just doesn’t happen.
Tier 5 spans from level 17-20. Characters unlock their capstone abilities at 20 which adds quite a bit of gnarliness to their bite. Spellcasters have access to their most powerful spells. The number of options available when creating a character of this tier takes even seasoned RPG players an hour for a rush job. Combat is extremely lethal leading to a lot of careful planning. It is strongly advised that players know their characters well and GMs should have a strong grasp of the rules.
At this point there should be no limits on the stories you can tell. Rewrite time, prevent or cause an apocalypse, or just enjoy some schwarma. Why not…
Characters in this tier: Q, Superman, the Hulk, Santa Claus, Zeus, Thor.