Forgotten Realms: Elminster in Hell (Elminster #4) Book

There is no greater blasphemy than this...Whether the Lady of the Weave heard and assisted him or not, life ahead was not going to be pleasant for Elminster Aumar. He was going to have to spend all of his magic healing this rift, for the love of Toril that so seldom loved him, be burned and blasted in the doing, perhaps fail and be torn apart - and if he succeeded, his reward would be to plunge at the last down into Avernus, bereft of spells and defenseless. Yet his duty was clear. Hell thirsts for power, and what power the great Elminster holds. What a prize this mighty soul must be. To what depths will the malevolent forces of the inferno sink to gain that prize? How deep is Hell?