Defeating a Rift Boss after opening rifts the natural way makes the autosave of passing a day kill the game

The Finale of tracking this bug, so it seems.

Playing as Wanda and defeated Celestial Champion, I gived an enlightened shard to the Cryptic Founder (Wagstaff) and lunar rifts started appearing in the constant. Said before maybe it crashed because they were opened the natural way, but nothing happened!

That's until Deerclops appeared at the same time a lunar rift was active. Defeated the Cyclops, it mutated into a Crystal Deerclops, and after a long fight with no planar damage he was killed a 2nd time. 1/3 Wagstaff appears to congratulate me and then he leaves.

Everything fine nothing changed, until I got to my base. Spent the night near my campfire heating up until morning came and the game crashed.

So it wasn't neither the rifts opened the natural way nor the day-counter being too long, it was WAGSTAFF having a good time after seeing me kill Crystal Deerclops. I do believe this happens with any rifts boss defeated but we finally have the exact steps to reproduce it.