How can you get to bitter aerie as Saint?

[Helion]

Apparently there is an echo up there, it's the last one I need to reach karma X, but I have no idea how to get up there. The upper gate to submerged superstructure above access shaft (the one on top of moon where you see all the karma symbols on the fancy paintings) is closed and the lower one (The one where you enter as Rivulet) seems impossible to get to because even when I swim straight down without dashing I am not even close to getting there without drowning. Are there any paths I missed or something? I'm a little lost, ngl.

[Redlegoguy1]

There are supposedly some extra tunnels for saint that are not present for other slugcats that connect to Aerie. I don’t know exactly where they start but I believe they’re connected somewhere near the memory arrays. I haven’t done it myself so that might not be 100% accurate, the wiki map is up to date for the region though so you can check that if you don’t want to find it yourself.

[Deerbeetledog]

(btw the bitter aeries echo is supposed to be an easter egg for saint, it is not required fot completion, and actually it is recomended to go after it only AFTER you get 10 karma)

[MadArtillery]

With two bubbles you can get into the underwater zone as gourmand so if you somehow come by bubble weed and get it to the dive point without expending them, somehow, you can probably get in through the underwater zone and use the exclusive pipes. Good bloody luck though. I gave up trying on gourmand because an aquapede was camping the entrance.

[MozarteanChaos]

there's another echo remaining in the world that you can visit instead, if you like.
if you're determined to go for the bitter aerie (perhaps for the challenge of it), nobody can or should stop you, but if you just want to reach max karma you should probably search elsewhere.

[蒼天之心]

Saint have another way,not in the water
you can check it in wiki
https://static.miraheze.org/rainworldwiki/a/a8/Map_MS.png