No worries! You don't need to include a ZIP of art or anything like that. Just credit me in game and tell the user that the art is licensed to you under the CC-BY-SA 4.0 International license. You can copy this sample text if it helps:
"Thank you for playing [Insert Name of Game]. The art for [Insert Name of Game] is sourced from #NotZelda Overhead Adventure Tiles by LUNARSIGNALS and licensed under the Creative Commons Attribution-ShareAlike 4.0 International license."
Oh! I see now.
So "share" just means make it easy for the player to find the source of the assets (e.g., via links and artist information in the credits and text file, etc.) so they can also purchase them if they wish.
Awesome. Thanks for the clarification!
To be specific, the "Share Alike" (SA) clause means that if you make derivative work of the CC-BY-SA artwork, then you should share this derivative work under a similar license. The general understanding is that a game using this artwork is not a derivative work, so in this case you only need to give attribution (BY). If you create new art assets based on this artwork though, then you should share it under a similar license. Your own art assets which are not derived from #NotZelda are not affected by this license, so they can stay proprietary.