When i first read "Lord of the Isles", first book in this series, i was convinced that Drake had decided to see if he could out-Jordan Robert Jordan.
And there are some similarities.
But Drake has a more mordant approach and wit than Jordan, and isn't afraid to have a little fun with the conventions of the quest-fantasy genre... and he does.
As before, he takes his core group of adventurers -- Garric, Cashel, Ilna, Sharina, Tenoctris and company -- and sends them by ones and twos on separate quests of hair-raising difficulty and (in many cases) grusomeness. But all of them (even the grim and apparently humorless Ilna) find occasional causes for humor, gallows-style or otherwise, and for moments of beauty and happiness among the violence and dangers.
Of the bunch, i'd say that Ilna -- who's had the hardest life of the adventurers so far -- ends up the best off in terms of Good Stuff accumulated in her quest.
The various quests -- Cashel's to find the sorcerously-abducted Sharina, Ilna's to find a way home after being marooned with companions, Garric and Tenoctris's to lay to rest a magical menace to the Kingdom if the Isles -- all SEEM unrelated, and have a habit of suddenly turning into something other than we thought they were, but looks can be deceiving in this sort of fiction, and the grand finale when Everything (almost) Is Revealed is quite satisfactory.
I want to make it clear that following is a High Compliment from me, reading this story was in many ways like playing one of the best-constructed of the old text-only computer games; everything dovetails nicely, and an apparently-unimportant action taken or not taken on one quest may have a huge effect on all of the other players' efforts, and one important clue missed anywhere could mean ultimate and horrible failure.