Actually, the Prince AU and the Knight AU were originally separate, but are often fused together to make the Prince Knight AU(and if memory serves me correctly, @LightDancer365 proposed the fusing of the AUs in the first place)

In most stories, this and the Disorder AU take place in the same timeline, creating the Royill AU(credit to Dancer for the nane lol)

This AU revolves around Shieldy and his life before BOTO. Because he is a shield, I headcanoned that he lived in a castle town, as a knight in training(the idea he was a prince came later). This AU has multiple storylines Dancer and I created, though all of them(except one) lead to Shieldy getting banished from his kingdom for one reason or another. After being banished, he finds Party Hat and Chocolatey(see Disorder AU or Childhood Friends AU(not published yet)) and they stay together until the main plot of BOTO starts.

Because the Prince Knight AU stems off the Prince AU, anything that happens in the Prince AU can happen in the Prince Knight AU as well.

The main AU (I think? It's the version we use the most):

- Shieldy is a prince who received knight training in order to teach him discipline

- He finds POWs in the dungeon while exploring

- He helps free them and is subsequently banished

- Briefly meets with Chocolatey; then meets and stays with Party Hat/Chocolatey until BOTO starts

More about the AUs:

-The Knight AU is to me, the most linear because the basic storyline is that Shieldy is a knight, but was banished due to being a childish troublemaker. But to be fair, I focus more on the Prince and Prince Knight AU, so there aren't many details for the Knight AU.

-Being a knight and/or prince, Shieldy has seen a LOT of shit. I realize this doesn't perfectly match with his canon character, but this is an AU. (Who knows, perhaps he age regressed to cope ahaha)

-In the Prince Knight AU, Shieldy's kingdom goes to war with Princess Diamond's kingdom at one point, but being the pure child he is, Shieldy saves Princess Diamond when she is in peril. Of course, he gets in trouble for this because Princess Diamond is from the opposing kingdom.(This paticular detail was made by Dancer)

-In a storyline of the Prince AU, Shieldy is separated from his kingdom because some people kidnap him(cuz yknow, he's a prince). He escapes, but can't find his way home. 

-As you probably know, servants in some castles weren't treated the best. But Shieldy treated them well.

-In all storylines, Shieldy is away from the kingdom by the age of nine.

-Shieldy is quite infamous for being banished.

-There is kind of a scrapped idea in the Prince AU that Princess Diamond is Shieldy's big sister, but I dropped it because it messed too much with the canon(see 'Miss You' for a short story around this idea!)

-There is also an (joke) idea Dancer had, that Prince Emerald is Shieldy's big brother, but this hasn't been expanded on.

- Realistically, Shieldy would've been executed for freeing the prisoners because it's literally treason, but obviously I can't kill him lol. So he gets banished instead. (see 'All The Right Reasons' to watch him die ig??? lmao??)

- Yet another idea I had is that Shieldy doesn't remember his past due to repression or amnesia. 
     - When he's about to get executed for treason, the prisoners he helped stage a distraction and get him out, but he gets lost in the chaos and suffers an amnesia-causing injury.
     - Alternatively, when he gets kidnapped, the same thing essentially happens. Only difference is that his kingdom isn't out to kill him lmao

- I named Shieldy's kingdom 'Lykke' because it roughly means fortune...in Danish. For some reason I thought it was Latin? In any case, I'm considering renaming it to something in French because Canada.

If there's an idea you have for this AU, tell me, I'd love to hear it :0 (And Dancer, if there's anything I missed, tell me XD)

Also!! If something doesn't make sense/if you have any questions please say something about it lol

And now, for a few pictures (they're only of the Prince AU though lol)(Ignore the red writing lmao)

Shieldy's headcanoned parents, Sword and Treasure Chest

A small comic a a

And perhaps more pictures to come in the future!

Aight, that's all I have to say for this AU, thanks for listening ;0 <333