Have beaten the False Knight, which took probably 10+ tries, haha. Found a small area that I can't really go into because it's pitch dark. Some locked doors. I saved up enough geo to buy a small key, thinking the door to the right would make me progress. But there was just a priest that told me I had no regrets.

Found an area called Greenpath, but I can't really do much there either. Go around and kill some foes, but maybe I can't get to the proper areas there, because I'm not able to jump far enough. Can't buy a map for the area either (I've tried many times, but no go despite there being notes about being able to do so littered around). Where am I supposed to go?

This is what my map looks like for now

I have upgraded the Nail twice (last with a Pale Ore), have defeated some bosses: False Knight, Hornet and Crystal Guardian (if that was a boss). Thought I faced a boss in the Soul Sanctum, but apparently that was "only" a soul warrior, a mini-boss of sorts. I get completely wiped there in seconds, and the shade is left in the room, which makes it much harder, having to fight two enemies. The whole room is basically nuked. Tried to take on the Mantis lords, but get nuked in seconds there too. Presumably have to fight all three, but I can barely get a hit in on the first one before dying. And travelling there... holy shit. It's like 10 screens away, through many tough enemies. I gave up on that one, and the soul area.

Have the Dream Nail (500+ essence now), the dash and wall climb ability. Apart from these impossible bosses, I can't get anywhere else it seems. In Fog Canyon a stream of what looks like oil is blocking me off from the cartographer (jellyfish area), and it's the same somewhere on the other side of the land. There are some shaking floors that I can't get through here and there. Have found the Royal Waterways and done what I can there (I think), including getting a map. Have 7 health skulls and extra soul capability, but only have 4 notches for charms. I use the compass (so I know where the hell I am), the gathering swarm (other 1-notches seem less useful), and the charm that increases soul collecting.

There is a switch in Mantis Village I can't get to, but I couldn't figure out a path I hadn't taken, everything seems to be cleared, except that when I change screen at some point down there, I see another mantis dude behind a locked door.

Tried to get aaaaaall the way east in Crystal Peak, but looks like I need to fly to get across the wide floor there. There is a grub behind (probably) the shaky floor, but otherwise think I've cleared it now.

Have taken on 3 (iirc) grave stones, and after some struggles defeated them. Presumably I can take on a whole pack of those guys east of the essence lady too. Accidentally 'farmed' a woman called Joni, so hope she isn't important. Noticed the "Listen" text when the Dream Nail animation was running (and no reloading in this game).

Where to go from here or what to do? Currently stuck in soul sanctum, but it seems so impossible. Lost 1400-ish geo earlier, so when I went back this time I deposited what gold I had with the bank.

(Took on the more impossible soul twat this time, behind that once-locked door, so that is where my corpse currently resides)