Potions can easily be made, if the herbalist has the information. Here are a few
potions that you can make.

Potion Type            | Re-Agents (In this order!)
-----------------------|---------------------------------------------------
Potion of Experience    | Sage, Ginseng, Mistletoe, Nightshade
                       |
Simple Potion of Death | Nightshade, Mandrake
                       |
Potion of Revin        | Nightshade, Mandrake, Mushroom
                       |
Potion of Might        | Ginseng, Prickly Pear, Sage, Lead
                       |
Potion of SShot        | Sage, Brine, Copper
                       |
Potion of Speed        | Glow Moss, Copper, Mushroom
                       |
Potion of Magad        | Elemental Fire, Silver, Glow Moss, Prickly Pear
                       |
Potion of Asini        | Lead, Nightshade, Black Powder
                       |
Potion of Full Healing | Elemental Fire, Ginseng, Mushroom, Elemental Ice
                       |
Potion of Masculinity  | Ginseng, Saltpeter, Glowmoss
                       |
Potion of Femininity     | Ginseng, Saltpeter, Mushroom
                       |
Potion of Neutrality   | Ginseng, Saltpeter, Glowmoss, Mushroom
                       |
Potions of Reversal    | Sage, Potion of Femininity, Potion of Masculinity
                       | Sage, Potion of Femininity, Potion of Neutrality
                       | Sage, Potion of Masculinity, Potion of Neutrality
                       
Some Re-Agents need to be made. If you wish to make a potion which needs one 
of these, then this is how its done.

Resulting Re-Agents    | Re-Agents (in this order!)
-----------------------|-----------------------------------------------------
Elemental Fire         | Gold, Black Powder
                       |
Elemental Ice          | Silver, Brine, Nightshade
                       |
Black Powder           | Saffron, Saltpeter, Coal
