Searching for a mario 64 rom hack?

i recently remembered playing a strange romhack of mario 64 when I was a kid, can someone help me find it?

Back when i was younger (around 7 years old) my dad owned a Pc where he installed a N64 simulator. He installed a bunch of games on it and I especially remember playing Mario 64 and Majoras Mask on it. I was very familar with the games. however there used to be a game wich had exactly the same graphics as mario 64 but there wherer a lot more playable characters. I especially remember playing with Luigi. And it had a diffrent feeling to it. I remember thinking it was some kind of sequel to SM64. I will try to describe everything I remember. Gameplay wise it was just like SM64 but i remember it only taking place on a open field. There was gras and some Trees here and there. The enviorment seemed to be very wide and kinda empty. The game also played during night time and sunset. I dont know if there was any goal or objective. I only remember that i enjoyed running around and explore the place. I just recently remembered this and I am not sure if my memorys are playing a joke on me or if my Dad actually installed some sort of SM64 hack. I already searched quite a lot and cant find anything close to it. Maybe there is anyone who knows more?