Alchemist

In your Home Camp you will be visited by the Alchemist. She provides the shop and will give out a special barter offer, where you can exchange items for shells or incubators.

The barter offer is reachable by clicking her special air ship that docks near below your home map. The offer is on a cooldown, so you can do this once a day or less. Do not forget to open the barter dialogue after giving away the items to claim the bartered items.

In the shop you see different tabs of item categories, including the special ruby offers. Items for rubies at a discount. As all true merchants, the original ruby prices might seem outlandish. You should make sure, the offer is actually that good, before you buy.

As you continue to progress in the game, more and more items will become available in the shop. You see new items indictated with a ! and need to unlock them. Be careful, since there is no confirmation when buying.

Some items increase in price after each purchase up to a capping. Some do not. Some might reset after playing and buying other stuff for some time (it is claimed this is a bug).

Keys, Safes, Chests, Gargoyles (they are closed!), Nymph Shells and Nymph Incubators have a max cost. The capping for nymph shells is rather high, so one might think they do not have a capping (2.5k and 5k for uncommon and rare).

When there is an event (there always is one), the shop might offer special event items. And if the event has its own map, this map has its own shop.