When entering a Shop or Secret Room, if Greed spawns, the OverrideData of that RoomDescriptor is set to a Greed layout, which causes Greed the replace the shop. Currently it isn't possible to know in advance if Greed will spawn, and replace that OverrideData with a different RoomConfigRoom. Some sort of callback to make this possible is needed.
When entering a Shop or Secret Room, if Greed spawns, the OverrideData of that RoomDescriptor is set to a Greed layout, which causes Greed the replace the shop. Currently it isn't possible to know in advance if Greed will spawn, and replace that OverrideData with a different RoomConfigRoom. Some sort of callback to make this possible is needed.