Well, I don't know your game. I assume there is a tilemap? Like I said, these are two different approaches:
1. Create invisible sprites on frozen tiles with the required physics properties.
2. On every tick compare the tile under the character. If it's frozen - temporarily change the properties of the tilemap or behavior. We do this in our game - when walking on ice tiles, 8direction deceleration is reduced, so the character is sliding.
Just wanted to say Moonstone island looks really cool and its inspiring! Any advice for a dev starting his journey?
I found a solution and wanted to share it here in case anyone else needs it. I discovered "Families" are a way to group similar objects together and you can add behaviors and conditions to them so I did that for the floors. Then the simple condition of whether the bullet collides with them. I was able to get some effects working, but I couldn't get the sliding effect when walking on it.
I tried to reduce friction and increase acceleration. Both objects had the Physics attached to them as well. The mechanic is working which is the point.