Gnar Super Galaxy skins recall is audible map-wide when vision is maintained.
Pretty straightforward. My entire team and the opposing team encountered this our game. Anytime Gnar would recall, regardless of where you were looking on the map -- if Gnar was in vision, you could hear his recall audio.
I thought I was crazy at first and was like "Wait, is gnar close to me? I can hear his damn backing audio.." But nope. Looked on the map, and found my friendly gnar recalling under his tower.
Then afterwards, I decided to test it again -- Looked bottom lane while he was top as he recalled..Yup, can still hear it. Asked my entire team -- they could as well. Same for the enemy team.
Seems like a minor silly bug. But i've still reported it. Difficult to with the bug tool though since his Super Galaxy skin isn't listed yet.