Use the following trick to get unlimited Master Health Elixirs, Will Master Elixirs, Silver Keys, or anything else that can be found in chests, Demon Doors, etc. In order to do this, do not pick up any Silver Keys or do any Demon Doors throughout the game until you get to "Find the archeologist" quest. It is your first quest in Witchwood. Accept the quest, then go to Witchwood. Go to all places that contain a Silver Key, potion, or item desired. Get all the keys, potions, items, etc., then Hero Save. Load the game, go to Witchwood, and repeat.