Koss is one of the first heroes you'll get in Nightfall. He's a main part of the chapter's storyline, eventually part of a soap-opera love triangle. Hey, chicks dig scars.
Dunkoro is the second of the first three heroes you'll receive in Nightfall. He is generally thought to be a fine monk, certainly an improvement over Alesia the henchman, yet further monks prove to have better AI for healing.
The third of the original Nightfall heroes, Melonni proves to be an astonishing ally. Sometimes, it seems her AI was developed specifically as that of an easily-distracted village girl, running to the other side of the map at every sign of something shiny.
Jin introduces players to their first decision-based quest where you'll need to choose between her or Acolyte Sousuke. This transaction includes an entertaining cutscene where we get to see truly how whimpy Sousuke is.
Sousuke is the other half of the Zaishen Elite quest where you will first encounter the decision to choose between heroes. As in all hero decision quests, if you choose Sousuke, it will prevent you from gaining Acolyte Jin as a hero until the end of the game.
This young Vabbian princess is full of attitude and spunk, but that doesn't prevent her from being an effective hero with AI sometimes more viable than the elder Dunkoro.
Olias is only one of two heroes completely dependent on the integration of another chapter. You'll need Chapter 1: Prophesies to unlock the quest used to obtain Olias, but he proves to be an easily-obtainable ally who is worth his weight in minions.
As with Olias, Zenmai is the second chapter-dependent hero in Nightfall. She is only available to those players who have Chapter 2: Factions included on their account. Not until much later in Eye of the North will you have access to another Assassin hero.
Zhed is quite the character. Not only is he the first (of several) heroes of a race other than human, but he lets us all know of his disdain for what he calls the "two-legs". He also seems to have the same AI problems as Melonni, venturing randomly across the map at the most inopportune moments.
In the second quest regarding a choose-your-own-hero scenario, Margrid the Sly displays her Corsair attitude both in cutscenes and during battle. Choosing between her and our next showcased hero (Master of Whispers) dictates storyline changes that carry through a good portion of the game.
This mysterious fellow is the second option in the Mysterious Message quest where you choose between Margrid the Sly and Master of Whispers. As with Margrid, choosing MoW guides you on a different storyline path which most people feel is more difficult than Margrid's.
After being with (and without) Koss for so long, it's nice to know you finally have another choice when it comes to Warrior heroes. The worst part about choosing Goren in yet another hero-option quest is the exclusion of our next showcased hero: Norgu.
Oh how we love Norgu, and if it weren't for a certain better-looking Mesmer you'll get in Eye of the North, we'd keep him in our group forever. Being the consummate thespian that he is, his quests and general party demeanor make for an entertaining experience.
The General is your first experience with a Paragon hero in Nightfall. He was once Warmarshal Varesh's right-hand-man, but for some reason, decided you would make better company. Curiously enough, in Eye of the North he learns a second profession to make him a Paragon/Ranger when you face him in the Norn Fighting Tournament.
At one time, Razah was the most sought-after hero known to players. He was only accessible after beating Nightfall and gathering a collection of rare stones found only in the Domain of Anguish. Well, inevitably, since then he's been made available through the completion of one very simple quest. Regardless, he's a formidable ally and well worth the quest's completion.
Ogden is one of the first heroes you'll obtain towards the beginning of Eye of the North. This dwarf is a fair healer, sometimes forcing you to dust off your Dunkoro or Tahlkora, but his gruff grumpiness makes for some entertaining times. Strangely enough, since he and a few of the earlier EotN heroes are so crucial to the storyline, you'll notice him in cutscenes with your party, even if he's not in your group.
Vekk is another of the initial heroes you'll obtain in Eye of the North, and he proves to be quite useful with his AI. In cutscenes, you may recognize his voice as that of Maurice LaMarche, who is famous for his work as The Brain on the Pinky and the Brain tv show.
Ahh Gwen, how you've grown. We first met Gwen as a small child in pre-searing Ascalon, way back in Chapter 1: Prophesies. But now she's all grown up and feisty as ever. Her hatred of Charr makes for some pretty entertaining cutscenes, as well.
After being with Razah for so long, you'll be reluctant to part for the likes of Xandra, but she might surprise you. Her AI works fairly well, comparable to Razah's, and she won't give you nightmares like he will. Quite the contrary...
By the time you get Kahmu, you will be so glad to rid yourself of Melonni, you will kiss him on his bald head. He (as well as Xandra) are the only two heroes that you must unlock through the Norn Fighting Tournament.
Jora is an exceptional hero, in more ways than one. Her AI as a tank is superb, but interestingly enough, the weapon and shield you give her actually scales up to meet her larger, Norn size. The only other case of this happening is with Vekk, where the items you give him actually scale down.
This Charr outcast still has some issues with humans, but he's willing to fight by your side for the greater good. Just make sure to keep him away from Gwen. For his sake, I mean.
Anton is an assassin you get in Eye of the North which doesn't actually require the implementation of Factions, even though assassins are native to Factions. This can be exciting for those who don't own Chapter 2, yet it is important to note that Eye of the North only has 10 assassin skills.
Unlocked through the quest Give Peace a Chance, Hayda is a spunky Paragon who seems to have some sophisticated AI, as with most of the heroes you find later in the game. Resist the urge to say something to the effect of "Don't be a Hayda". It's already old.
Livia is said to be the sole reason many people progress into the Tarnished Coast area of Eye of the North. By the time you obtain Livia, you'll be saying "Olias who?" "Master of what?"