By my count, Justice Gorsuch has written nine opinions in cases in which an Indian tribe or member was a party. My methodology is imperfect–I searched the Supreme Court Database for "+Gorsuch & Indian". But I think I captured all of the relevant opinions. (Please email me if I am missing any.) This total includes majority opinions, concurrences, as well as dissents.
In each of these nine cases, Justice Gorsuch ruled in favor of the Indian tribe or member.
Here is my list: