The last of the spells that can be found in the necromantic spellbook Cryptichronos conjures a wall of bones.
Wall of Bones was mentioned in the article as being a spell that could be in the book and originally appeared in Oriental Adventures. It later appeared in 3.5’s Complete Arcane. Instead of converting from those versions, this is pretty much just a mash up of 5e’s wall of stone and wall of thorns.
As an aside, years ago I toured Rome’s Capuchin Crypt. Quite beautiful and definitely creepy.
You can find this on the Dungeon Masters Guild as part of Van Richten’s Notebook.
Welcome traveler from an antique land.
You hold in your hand one of Dr. Rudolph van Richten’s numerous notebooks. In his travels, Dr. Van Richten took copious notes that later led to the publication of his many Guides.
This is some of what he has seen. The unheard of monsters, who slither and bite. Wondrous items and and artifacts he has found, their mysteries yet to be unlocked. Of the vexing spells and enchantments he has encountered.
Seven monsters, six spells, and nine magic items!
Bestiary includes the allip, amorphous blob, bloody bones, cobweb golem, dry bones, skotos, and slaugh.
Spellbook includes amorphous blob, creeping darkness, crimson scourge, undead control, vampire mist, and wall of bones.
Magic items include the cloak of night, eyes of the undead, gauntlets of the ghoul, ring of lycanthropy, skull mask, spectre wand, sword of night, trumpet of doom and withering scythe.