3rd pov:
Once in a multiverse on the far side of the universe was the realm of nightmares and there lay the one and only bill cypher
after his encounter with the pines family, he got destroyed and reappeared where he was born the nightmare dimension which led him to go back to his roots, and through that, he gained new abilities such as shadow manipulation, hypnosis, mind manipulation, mind-reading and the 3 o's such as omnipotence, omniscient, and omnipresent but he is yet to use this ability he also had much more ability he learned.
so after he had all he wanted he use one of ability to search for entertainment that he could have and when he searched through all the galaxies/multiverse and found known he came up with the idea to reincarnate someone and give 3 wishes to that person so after that he went earth there he found someone that could potentially be smart with his wishes so he made that person die of a random cause.
Mort pov:
Today was supposed to be a good day for me just chilling and watching anime/shows but no it didn't go like that because right when I was watching my favorite anime my hero academia and it was getting to the good part I get struck by LIGHTNING and yeah after that I woke up in a void and there I met a floating triangle and I looked at it's cingular cyclops like an eye for a few seconds until it said....
3rd pov:
When mort was done staring at the triangle-shaped being. the being said hello mort my name is bill cypher and mort was shocked because this being was bill cypher and he watched gravity falls and was a fan of him he was also shocked to how bill cypher knew his name and the being said I'm looking for entertainment and I happened to stumble upon you so now I will give you 4 wishes what you choose for those wishes is on you. oh and also you can choose your appearance
Mort pov:
When bill cypher told me I get to choose the wishes I was happy because I have read novels of this happening so I said I want my appearance to be a fan art of you I saw on Reddit once so now for my first wish I want to have your abilities. bill cypher said yes but you will have to make deals like you make a deal with someone I will give you 10 copy's of my powers
(A/N: picture in the comment section)
For my 2nd wish I the ability of meruem whatever I eat like a beast I will get its power or ability
For my third wish, I want the ability of all for one (a character from MHA)
After that bill cypher said ok and I fell through the void and then......…..