The red elixirs are Liquid Voodoo juice. The woman who runs the place isn't sure what they do, only that Erzulie brings them into the shop and they seem to help people. There is a +10 bottle ($6) and a +20 bottle($10).
The green elixirs are health restorers. They can be drank (at any increment, meaning it doesn't have to be all at once) to restore health in the amount drank. There are two +20 bottles ($12 each).
The blue elixirs are medicines. When taken, they add whatever amount they contain of MP (medicine points) to your overall HP. They act as a shield buffer and will take hits without damaging your HP (it's like having a second health bar). They can only be used at full amount (all at once) and last for only the encounter. They cannot be used on bloodied party members and they do not restore any health. There is a +10 bottle ($12) and a +20 bottle ($22).
A deck of tarot cards (5 new cards) ($20). There is also a larger deck (10 cards) ($35).
Poll