So, I made a custom board that has a special location type. Rather than stable or unstable, these locations are "Destabilizing:" they are stable locations at the start of the game, but once the Doom Track reaches 6 they become Unstable and gates can begin opening there.
The problem is implementation. Originally I was going to have Mythos cards that had the "Alternative Gate" option, where one gate would be an unstable Location and one would be destabilizing. If the Doom level was below 6, you opened the gate at the unstable location; six or above, and you opened it at the destabilizing location instead.
The problem with this is that Strange Eons does not allow you to put two custom locations on the same Mythos card -- if one of the gates shown is a custom location, the other one must be from one of the official boards. Since the board I'm making is supposed to be usable without any of the expansions or even the base game, this is something of a problem.
Does anyone have any ideas that could solve this?