Health Potions
These potions recover you Health when you drink them, each potion recovering more health than the last.
Strong Health Potions can only be consumed by Knights and Paladins of level 50 or higher, Great and Ultimate Health Potions by Knights of level 80 and 130 or higher respectfully.
Mana Potions
These potions recover you Mana when you drink them, each potion recovering more mana than the last.
Strong Mana Potions can only be consumed by Sorcerers, Druids, and Paladins of level 50 or higher and Great Mana Potions only by Sorcerers and Druids of level 80 or higher.
Spirit Potions
Spirit Potions are special in that they recover both your Health and Mana when you drink them. Currently the only Spirit Potion is the Great Spirit Potion, which can only be consumed by Paladins of level 80 or higher.
Skill Potions
These potions are unique in that they temporarily increase your skills when consumed, depending on which potion you drink. Rather useless due their rarity, most people just use them as decoration.