The way I first understood this to work is that each unique realm is based off of the Biome, Major Card, and Difficulty of the realm. So you could have up to 4 unique Forest Hunt realms in your game for example (one for each difficulty level Easy - Extreme). And no matter which portal you used, or which realm you used the portal in (Fae portal or crude), it would take you to that realm based on Biome/Major Card/Difficulty. (as long as you didn't check the Reset Realm checkbox and reset).
However, my game is in a situation where I have two seemingly persistent Forest Hunt (Extreme) realms. The latest one was created from my abeyance realm, using a crude portal, and takes me into a Forest Hunt Extreme realm, with blood moon minor card activated. This portal has no issues at all as long as I use that portal that I created from my abeyance.
My thinking was if I created a new portal in another realm that led to that Forest Hunt Extreme realm it would go there, however it is taking me to an older Forest Hunt Extreme realm that has explored POIs. One that I visited before, but the newer one should have overwritten it when I created the new portal? All portals in my abeyance that were tied to that old realm have been deleted.
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