The Runic Rocks sound fun and interesting - I always enjoyed the aspect special tiles added to seasonal events. Based on the name, number, and description it seems like the Runic Rocks are NOT these
Image from the New Year 2020 Sneak Peek Discussion thread, but pasted in here for ease of reference. In that thread they are called “Icons.” So…is there any clue as to what function Icons may serve in the game?