Shop in a Bottle

Effects
Once consumed, a Crawl Space will spawn, when entered, a shop will be there, just like normally finding it in the floor. This can be done in the same room and even in the secret shop itself multiple times.

More than 100 secret shops can be spawned in a single room, however the new shop entrances will start to cover old shop entrances. The covered shop entrances are still accessible though as leaving the room and re-entering will shuffle which entrance is on top, making it possible to access entrances buried under other entrances.

The crawl space will not count for the one crawl space hidden on each floor.

It is currently unknown how many times "Shop in a shop" can be done until the game either breaks or crashes. However it is greater than 100 times.