Whatever. I'm just gonna do it on my own completely from memory.
A Beginner's Guide to Experiencing Grimdorks
Grimdorks Art
The best place to find Grimdorks fan art is the Grimdorks tag on MSPAbooru: https://mspabooru.com/index.php?page=post&s=list&tags=grimdorks&pid=0
The MSPABooru is always a wonderful source, as without it a majority of Homestuck art would probably be lost media because of the shuttering of the original MSPA forums and the laissez-faire approach to media preservation of Tumblr and DeviantArt.
I would estimate this contains a majority of all surviving Grimdorks content stretching back to mere months after Homestuck began, with only a few blindspots.
Grimdorks blogs
https://www.tumblr.com/grimme-and-specs this is pretty much the only modern tumblr blog dedicated to johnrose.
https://wunderscheisse.tumblr.com/tagged/johnrose This is also a pretty massive source for large quantities of johnrose.
https://x.com/vangabound this dude's twitter is cool. they release a Grimdorks comic every april 1st. I think they've done it for 3 years.
I'm probably missing a lot of active/inactive Grimdorks accounts, but those are the big ones off the top of my head.
Grimdorks Fanfiction
The John/Rose and June/Rose tags on Ao3 are pretty reliable. John & Rose is of course more crowded, but still contains some real gems. Of course, many of the older Grimdorks fanfictions are squirreled away in the depths of fanfiction.net. In my experience a lot of them aren't worth dredging up, but if you're really starved that's an option. Don't use wattpad.
That's about all I can think of for now.
(Source: A deleted tumblr blog called "Harlegrim" circa 2013)
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Website: https://harryhinderson.neocities.org/