Super Mario Land 64 was a hack created by awesomelukeyproject (Eventually more known by the name 'Cybertanuki') which started development around 2007 and 2008, as a very basic sm64 hack at the time, mostly a reskin with a few new levels. However, as the time passed by, the hack began to get a more consistent form, as it was now fully customized with a plently of new levels that were teased on the Kuribo64 thread of the hack (Will be posting the published images soon).
Eventually new developers and colaborators joined the project, such as Dudaw, mariosan (Apparently for a short moment), Ankle Destroyer and even Kaze Emanuar (At some point). However the hack was cancelled, with around 30% complete, in sometime around Late 2018 and Early 2019. Cybertanuki had a channel where he used to archive his old videos, however in December 2023 he deleted his channel for unknown reasons.
Link to Cybertanuki's archive.org: archive.org/de... (Has most of the old videos from around 2012 all way up until 2018)
This build was leaked for a brief moment around 2015/2016 by Darkspire17, after him and mariosan managed to get a build from WWArea (Which is supposed to have more updated builds of the hack but it's unknown if that's the case), the video is currently unlisted.