User blog comment:VedranTheII/Pretentious Diaries 2: What tricks would you teach your Aura?/@comment-4010415-20150720024504/@comment-24198837-20150721003519

Thing is, max level is 20, where your group should be fighting CR 20 monsters. A good group of max levels could probably kill a CR 23 or maybe even a CR24 if they got really lucky. My group's last huge campaign concluded with us, at max level, killing a CR22 without loosing anyone. We were all on the brink of death, though.

Cthulhu is CR 30. If you didn't see his "Unspeakable Preasence" ability: whenever you come within 300 ft of him, you have to make a DC 40 will save (which is stupid high) or DIE INSTANTLY.

Then, when he dies, he turns into mist and re-forms almost instantly. This revival staggers him, and the only way to actually banish him (as he can't be killed) is to 'kill' him AGAIN while he's in this state (which lasts a consederable twelve rounds at most, but could potentially last as little as TWO). If the time passes and he's still alive, he regains full awarness and hitpoints, and the entire process must be repeated.

He's basically just stronger than mortals can ever get, and even at max level, you need lucky rolls to even live long enough to swing at him. Then you literally have to fight him twice or more when he's far stronger than you'll ever be.

TLDR: If you ever play pathfinder and your DM wants you to fight Cthulhu, you run and hide. Maybe you'll be one of the last he kills, because 99/100 times, even you're entire planet can't win.

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There is a system called mythic, which is a 10-rank additive system seperate from levels, and a level 20 Mythic 10 is technically level 35, because Mythic levels are worth more than class levels. It's confusing, but to put it simply - when you're that powerfull, nothing short of a literal God scares you. And they aren't that far above you at that point anyway.

But in the lore of Pathfinder, hardley anyone's ever even reached level 20, much less Lv20 Mythic 10. That's literally unheard of, and would (in lore) likely happen only because of direct divine intervention or similar.