Open world
I played more than three hours today (for a total of 24 hours of play time), so I made huge progress again.
I began by finding Isma's Tear, which allows me to swim in searing and acidic pools, finally answering the question that I had about traversing certain areas where it seemed obvious that I had to swim over. I thought that was the case anyway, but I kept telling myself that it wasn't, for whatever reason. It should have been obvious. This being a metroidvania and all, "suit upgrades" (like how the Varia Suit allows Samus to enter areas with extreme heat) are nothing new.
So, immediately thereafter I travelled to an area that I had passed by many times, where Isma's Tear was going to be useful. Here, I found some more Essence.
This was followed by me finally finding Cornifer in Fog Canyon. I had heard him hum along around this area many times before, but there is this "black barrier" (that I still haven't gotten whatever it is that I need to get rid of it) blocking the way.
Traveling a bit further I found this character... who I had to kill, breaking a part of the seal.
I need to point out here that right in the beginning of the game, where I passed by a certain room (which I think was called "Temple of" something or another), I immediately felt that the final battle would take place there. It's a very common video game trope for the final destination in a game to be back where it began, after all. I have intentionally not returned to that place ever since, and while there have been numerous hints indicating that I was right, now that I have broken the first seal, it's plainly obvious.
Incidentally, when I went back to the Forgotten Crossorads, they seemed to be "infected" with some orange goo. There was an area that was even impassable, so maybe it won't be a simple matter of returning to the temple once I'm ready. Either way, I want to explore all other loose ends that I can find first (which seem to never end) before I make an attempt on the final boss.
As luck would have it, I found yet another area right after: Queen's Gardens. No matter how often I kept telling myself that I've been to every place in this game, new areas keep opening up all the time.
I then found a new ability: Howling Wraiths. I have tried it out but haven't found a practical use for it in combat yet. Might be able to repel multiple foes closing in on me with it. I have a feeling that there must be at least one more ability though, as the black barriers are still blocking my way everywhere.
Then I found Cornifer again, and now for sure, I have obtained the maps of every area in the game. I know because I obtained an achievement called "Cartographer", and when I returned to Dirtmouth later, Cornifer was peacefully sleeping in the shop. This must be it. I'm finally nearing the end of the game.
Then I found the Love Key. I have a hunch where it might be needed...
Then I got the Essence in the Queen's Gardens.
Followed by the Essence in Greenpath.
I then stumbled on the grave of Marmu, who took me a few tries. He basically bounces around the stage in an erratic manner that is difficult to predict (it may even be random). For the first time in the game, I felt the need to actually change up my Charms, so I went with Dreamshield for extra protection, Heavy Blow to push him further away from me after hitting him (he comes in fast, so sometimes he hits me even if I hit him first), and Mark of Pride to allow me to hit him from further away and thereby keep my distance. Once I changed the Charms, I defeated him on the second try.
I think I may then have discovered the last Stag Station, because the stag told me that he had found his birth place, the Stag Nest, where I obtained this fragment of a vessel. I think there may be only two more left for me to collect (same for Mask Shards).
The Stag Nest is located in the Howling Cliffs, so I used the opportunity to collect the Essence there.
After that, I defeated another warrior, Gorb, who I took down on the first try.
Now that I have all the maps, it's time to clean up with all the markers, objectives, collectibles, etc. So, I went down to Deepnest (probably my least favorite region because of its dark spider-y theme), to break the second seal.
I'm not sure what will happen if I break the third one, so I will leave it alone until I have done everything else that I could.
I also had to collect the Essence in Deepnest.
Finally, I finished my play session today by defeating another warrior: Galien, who I took down on the third try.