I'm fairly far into the game, and I have made it to the gate where I presume the Tome of Elixirs is stored (3rd level of cave near High Garendall), but it says I lack the key to gain entrance. Does this mean I need another key than the one recovered from the third level of the Learning Tree? And if so, where do I get this? I assumed that the key that let me into the general area of High Garendall was the only key in the game.
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