Reading Pile: Mystery Flesh Pit National Park
This is a bit of an odd recommendation as this isn't a comic or webcomic, but instead a collection of various artifacts that are all part of an amazing worldbuilding exercise that came to life on Reddit. Created by Trevor Roberts, MFPNP is an engrossing blend of alternate history, cosmic horror, body horror, existential dread, satire, and much much more. And once you start combing through the archives of fake brochures, government reports, old footage, and various advertisements documenting the history of the Park until its closure in 2007,you'll just keep falling down the rabbit hole of this oddly realized experiment.
The Flesh Pit is a geobiological feature discovered in Texas in the early 70's, and it's essentially an orifice in the ground for some creature beyond our comprehension. After various survey missions by joint American and Russian forces, a mining corporation eventually opened it up as a tourist attraction which in turn led to the site being absorbed by the National Park System. And yes, it even has a gift shop.
And yes, it also has a Hard Rock Cafe and a Burger King.
The various elements that comprise this experiment are also accessible via the Mystery Flesh Pit tumblr, where you'll find a healthy mix of brochures, speculative biology pieces, fictional paperwork, tourist photos, and other pieces of ephemera that all infer to the creepy hidden layers of terror that the humor hides so well. It's like if the entirety of Jurassic Park was filtered through the lens of Mr. DNA, and instead of possibly being killed by a dinosaur you might instead be randomly digested, crushed by a muscle spasm, or suffer the soul crushing realization of your insignificance in the cosmos.
One thing I really love about it all is that it doesn't follow a real linear story line as the 'found artifact' nature of the fiction is all randomized. A larger framework of the puzzle has been given, especially as at this point we now know about the disaster of 2007 where a mixture of incompetence and bad luck caused the deaths of over 700 people and the realization that if whatever is attached to the Pit actually wakes up then the entire world is screwed. There's still so many elements that are shrouded in mystery though, partially because science hasn't been able to explain certain aspects of the Pit and partially because we only get to see what has been found. It's an excavation of worldbuilding where new pieces are discovered over time, making this an experiment that just keeps on giving.
If you prefer straight up linear stories with solid plot structure and so on then this may not be worth checking out for you. Reading through dry government reports and tons of fake ads and the such may feel more like homework at times as well, but I think the mystery element helps to get past that feeling of drudgery. Like with most Lovecraftian horror, I have a desire to see how the cosmic terror is revealed and to try and understand how these things all fit together, so this is very much my jam in that regard. The little hints and inferred terrors have me wanting more, while the sheer realistic idiocy of human greed trying to sell a literal pit of death and despair as a vacationing spot helps dull the edge of too much existential horror.