This is the 6th in the "Star Revenge" Series of SM64 hacks. This hack is based around the idea of sm64 itself that you go into a taken over version of Peach's Castle and get stars from there to beat bowser, but as Luigi (or green/eco Mario, whatever you want)
The 1.3 version adds some updates to the camera and coin missions while also adding some pipes to get back from places you would be stuck in normally with no return to the rest of the level if you were f.e. collecting coins. Also comes with a new stars based around an mostly unused area in the hack.
This hack has 15 new main courses + side levels and 121 stars to get. Doesn't get too difficult but also isn't too easy.