a while ago i had an idea for a silly au, so im sharing that here
the au is called the 'hidden' au, but im thinking of changing it to the 'lost' au
basically, a hundred or so years ago, oceanus managed to successfully get poseidon off the throne, and not only that, but he also turned him and his family into mortals on land and so for a while they were just struggling trying to figure out how to survive, until they met sally amphitrite and poseidon simply befriended her at first while their kids didnt really care, before they all movd in together bc that just worked out and a while later poseidon sally and amphitrite all got into a relationship then bam. percy
the only person in poseidons direct family that was not turned into a mortal was kym, as oceanus felt like she could join him only realizing her family was missing a while after it happened, kym kinda joined him. she didnt care much for her family, they had hurt and outcasted her, but oceanus did not care for the ocean and atlantis as poseidon did, he dragged them down into pain and misery while he sat back with joy.
percy does not know the truth. he was told both amphitrite and poseidon (all the seafam probably have different names to stay hidden, maybe theyll be in danger if people actually know who they are) (sally knows who they are), and he was told theyre both his actual parents. so. hes confused on his parentage. a lot. but anyway hes still claimed, still claimed at the canon time, where the water healed him. when the water healed him, it gained the attention of both kym and oceanus, kym, realizing this kid was Strange, immediately claimed him. she didnt know in what way, but he had a connection to her family.
with oceanus now knowing there is a demigod that is the oceans favorite child and freakishly powerful, he wants percy. is it to kill him or get him on his side? who knows! not important!
i dont really know how percy would find out the truth, but im thinking something like, he somehow ends up in atlantis when oceanus isnt nearby (maybe when the princess andromeda blows up) and is instantly swarmed by the atlanteans who are like 'i dont know who the hell this kid is but you have the same energy as our rightful king and queen' and maybe he gets poseidons trident or smth?? but he eventually pieces together. 'wait. the married couple that raised me. that are my parents. ARE POSEIDON AND AMPHITRITE??'
and when he gets back, poseidons trident in hand, hes like 'someone fuckn explain' and so they do. meanwhile percy is losing his fucking mind because he was literally being lied to by his parents his entire fucking life
and also, since poseidon, the king, and triton, the heir, arent in atlantis anymore, theres no rightful heir or anyone who should rightfully have the throne. expect for percy. even though hes a demigod, hes enough of the sea to be in line for the throne (kym left that line when she was banished + she didnt really care for it in the first place)
anyway this au is mostly silly to me and i like thinking about it when im bored so uh. yea. have a new au idea. enjoy. send me asks if you have any