>>113987417Two books, yeah. Written by people on the crew, about ~150-200+ (can't remember) pages, really heavy on lore stuff.
One came about between the 2nd and 3rd seasons and is a guidebook "written" by Star and Marco about a lot of stuff in the show up to then. Star and Marco's Guide to Mastering Every Dimension.
The other is a book version of the Spellbook, The Magic Book of Spells, and came out between S3 and S4. It's what the last 13 Queens of Mewni (from Solaria's mother up to Star) wrote in the spellbook.
Both books are higher quality than my description makes them sound, pretty fun to read and are more than just a guidebook/spellbook. Ex. there are excepts from Star's journal, a map of Mewni, diagram of the wand, etc.
Despite my bitching about how the Eclipsa stuff is handled in the guidebook, they're generally really high quality and better than the later half of the show. They're worth checking out.
Also there are 4 original comic books (intended to be 8 since it's one story but they got canceled halfway through) and some comics literally just made up of text from the show and screengrabs, but understandably no one cares about those latter ones.