The Keeper of the Portal waits outside Candlekeep , at the top of the Way of the Lion. It is his responsibility to stop unwanted persons from entering Candlekeep. He demands payment of a valuable tome or book to gain entry. This book is gained in Chapter Six from Duke Eltan in Baldur's Gate. He takes no damage and is magic resistant. If you return to him immediately after Gorion is killed, are nice to him and beg for assistance, you can get 100 GP from him for free.