Alternative Character Interpretation: Entreri's For the Evulz moment from the main page. Alternatively, it's something of a punishment/warning to Regis, who faked having a contagious disease to try and get them tossed off the ship ("attempt to slow us down again and see what'll happen to the people around you" sort of thing) as well as being a form of twisted revenge against the captain of the ship for making him get off early.
Complete Monster: Akar Kessell from The Crystal Shard is the self-proclaimed Tyrant of Icewind Dale who formed a pact with Crenshinibon, the titular Crystal Shard, to fulfill his megalomaniacal aspirations. Even before finding the Crystal Shard, Kessell murdered his mentor, whom he considered like a father, on the order of a cabal of evil sorcerers in the hopes of gaining power and prestige. Ultimately nothing more than a loose end to tie up, Kessell was abandoned in the wastelands of Icewind Dale where he found Crenshinibon and set out to use its power to conquer Toril. Kessell would use the Crystal Shard to enslave countless goblinoid tribes and mind-control innocent women to be his sex slaves. Kessell soon grew bored and, against the advice of Crenshinibon, set loose his armies on the Ten-Towns where thousands where slaughtered, but, proving himself an inept leader, he was outwitted and defeated by Drizzt and the Companions of the Hall. Despite Crenshinibon being known for its corrupting influence, Akar Kessell proved to be a monster all along who was buried beneath an avalanche by the Crystal Shard when Kessell's own power lust grew too much for even the Shard to handle.
Critical Research Failure: Streams Of Silver mentions that fire can kill trolls, and that they otherwise regenerate from anything else. The text notes that more than one predator has been killed from the inside after dismembering and eating a troll as the troll regenerated inside its body. What Salvatore apparently forgot is that trolls can also be killed by acid...which is what stomachs use to digest the food humans and animals eat.
Foe Yay: The way Entreri reacts to Drizzt's rejection in "Streams of Silver" is just hilarious - like a disappointed fan boy. In fact, every time Drizzt and Entreri are on the same page expect Foe Yay to follow, especially from Entreri's end.
Fridge Brilliance: Drizzt and Entreri probably would have thrived in each others' bodies. It's noted at several points that Entreri would have prospered as a drow in Menzoberranzan, to the point where even the bigoted dark elves admit that he's drow in everything but skin color. On the other hand, if Drizzt were human he never would have had to put up with Fantastic Racism to begin with, and without the goal of earning a place for himself, his prowess might have made him grow proud...
On the other hand, Drizzt was born into incredible privilege, even by Dark Elf standards, and raised mostly by his contrarian father/ weapons trainer who did some work to shield him from the Always Chaotic Evil nature of the society. Enteri was a street rat who most likely became a sociopath because he grew up in an environment where he had no family and had to be absolutely ruthless to survive, perhaps their personalities aren't as unexpected as they might seem.
Ho Yay: Lots and lots of it. In The Halfling's Gem the captain and Drizzt get really friendly on their journey; culminating in the captain stating that Drizzt looks more handsome as himself rather than looking like a surface elf.
What an Idiot: Did that mage apprentice really think he could control a demon from the Abyss?