I have an idea for an Infinity Train mod, so I'll talk about it here. I won't make this a thing myself, since I'm already working on a pretty ambitious mod.
SPOILERS FOR BOOKS 1 & 2 OF INFINITY TRAIN
I haven't seen book 3 so please don't spoil it, and book 4 is forgettable for me so I won't discuss it much.
I think a mod title for it could be Infinite Funkin' with the logo in the same style as the Infinity Train logo and the beta logo in the game files of fnf could be replaced by the title in the style of the Infinity Train pilot logo.
Weeks will instead be called books to match the show, with the protagonist of each book playable. The text for the book and difficulty will be the same, but the white outline would be the glowing green in the Infinity Train logo. Each book would feature 3-5 songs going over important events in the story, for example in book 2 a song for the flecks would be there, but probably not the parasite.
Book 1 would obviously have Tulip playable. I think opponents would be the weird cockroach things from the wasteland, the Steward, The Cat, and Amelia. Mechanics could be a space bar thing similar to Hypno's Lulluby would be there for the cockroach thing, and the Steward and Amelia could borrow random mechanics from other mods by using the orbs. I can't think of anything for The Cat, maybe something involving getting the Randles in her pod or something, idk.
Book 2 would have Jesse playable, and later on Lake since Jesse isn't there for a couple episodes near the end. Opponents would be the Flecks, Lake, the Apex members, and Mace. Lake would be playable for the Flecks, the Apex, and Mace, since Jesse is absent during the times Lake would probably face off against the characters. Grace is missing from the Apex since she's busy destroying the new car with Jesse. The fight against Lake would be in the Family Tree Car. The only mechanic I can think off is for fighting Lake, the mechanic being similar to the fear mechanic from the Sonic.exe mod, the more it fills up, the more Jesse is covered in wood.
I won't do concepts for books 3 and 4 due to the reasons I said earlier so instead I'll do some cover ideas. Tulip and Lake could sing Phantasm, and Mace, Sieve, and Lake could sing Prey. Lake killing Mace would replace Sonic dying in Prey.
That's all I have to say about this concept, if you want to make this concept an actual mod, go ahead! Crediting me would be appreciated!