Gothic 2 is an example of what can truly be done with enough dedication and attention to detail.
Firstly, Gothic introduced us to it's own Radiant AI similar to the one Bethesda attempted to create in Oblivion. But while Bethesda failed, Piranha Bytes stood victorious. Npcs had daily routines, such as their jobs, rest hours, and even their own reactions to one another, and could initiate dialogue with each other at any moment without looking ridiculous like they did in Oblivion. Npcs in Gothic were programmed to react to player actions as well, such as if the player drew his weapon in front of them, they would react by drawing their own. Also, Npcs were programmed to become angry whenever you try to walk into their house or try to sneak by unnoticed. The developers did everything they could to make even the most insignificant Npc seem like a living individual in his own right, by characterizing them with their own unique personalities and reactions to various actions on the player's part, or in some occasions, those of other Npcs.
Secondly, Gothic had a faction based story. Meaning you had to choose to side with one of the resident factions and play the game according to their point of view, and help them to achieve their goals. Once a faction was chosen, various Npcs will react to your choice accordingly, depending on their relations with said faction. It's much more complicated than how I described it here, and it was a refreshing change of pace back in the day.
Thirdly, the Gothic universe is an unforgiving world in which you are nothing more than a tiny ant in giant ant farm with it's own rulers, factions and politics. The game genuinely makes you feel like the world wasn't crafted for you to exploit, but rather you are a lonesome man trying to survive in a hostile environment with only your wits to help you push your way up in ranks of society and become someone important. Also, the wilderness outside the camps is a dangerous one, with early game exploration often resulting in a quick death rather than some actual rewards. It serves as a harsh and above all realistic lesson in life, that achieving something great requires a lot of effort. Though once you do, the game rewards you handsomely, creating that wonderful "effort plus exploration equals reward" effect , that I love so much about sandbox Rpgs.
In short, Gothic took the tired old fantasy Rpg formula and added a special twist to it. Three years after the rather modest success of Gothic, comes Gothic 2 to improve on the original in almost every aspect.
The story now takes place outside the penal colony that was in the original, and with it comes the expanded world map that is literally twice as big as the old one.
The story has also improved tremendously, even though it's not terribly original, Piranha Bytes(I'll refer to them as PB from now on) made sure that the player will never be bored, with constant twists and turns in the story guarantee to keep the player guessing as to what happens next.
The writing is also solid. Though the game doesn't explore deep philosophical issues, the dialogues are mostly well written, well voice acted and entertaining to listen to. Even if it's just idle talk, the developers ensured that there will be plenty of hilarious dialogue options and equally hilarious responses. It's also strange that there is almost no swearing in the game even though PB had plenty of opportunities to add some. Despite that fact, I think that using less vulgar alternatives to express one's feelings are actually much more appropriate in this game since we are talking about medieval times, where even the common language was still far more sophisticated than today's street talk. The game also takes great care into making sure that character motivations are justified with more than just "he is evil" or "he is good" motivations. Even the supposedly good characters will still have some sort of personal gain to be had from helping the main hero in his quest, as well as the protagonist himself being motivated by common sense rather than bad writing skills - like agreeing to cooperate with Xardas because he saved his life, even though he is a rather dodgy looking fellow to say the least.
It may seem weird that I even mentioned the fact, but most games disregard coherent character motivations a bit too frequently, to the point where these games are considered endangered species by today's standards.
Then there is the combat which takes some actual skill, so mashing the attack button will most definitely result in your untimely death. Gothic 2, much like it's predecessor, allows your character to improve his fighting and marksmanship skills by receiving training from certain Npcs. At various pivotal points in your training your technique will visibly change, resulting in new and spectacular ways to swing your sword or increase the effective range of your ranged weapons, should you choose to level up your marksmanship skill. Gothic 2 also allows players to become magicians, although this path is a bit difficult to take at the beginning due to the fact that the magician order is one of the three resident factions, and unlike the other factions, they require a significantly greater effort on the player's part before allowing him to join their ranks. Though once you do, keep in mind that mages require an enormous amount of mana potions to cast spells. And even though you can still use swords and bows, casting spells will be your primary weapon against your enemies.
Speaking of fighting, the combat AI is very smart and challenging to go up against, while the path finding AI is terrible, and will cause enemies to get stuck behind bits of wall or even fall off cliffs, while at other times it makes them behave very weirdly, such as having a sudden urge to start climbing ledges in the middle of a fight. Though to it's credit, it rarely happens.
Gothic 2 also employs the "if you can see it, then you can go there" approach to sandbox worlds, by allowing the player to climb ledges Lara Croft style, and explore various "uncharted" parts of the map. Like for example finding a cave hidden behind some bushes, only to stumble upon a shadow-beast and get torn to ribbons. There are also some quests to be found while exploring the wilderness, many of which are quite interesting and offer very useful rewards, such as persuading an Npc to teach you a special skill or two. In fact, most quests in Gothic 2 have multiple solutions and some will even have unforeseen side effects and consequences that are much more than just cosmetic. Quests range from the usual Fed Ex delivery service (which are thankfully quite rare), to the much more interesting ones such as uncovering the location of the local thieves guild, and finding evidence to incriminate them - A task that is much harder than it would seem at first glance.
Lastly, the music is mostly very well done and conveys the atmosphere of the game quite perfectly. Even the combat music is different depending on the area you're currently located in. Which again, is a very rare occurrence. Especially if you compare this game to most triple A titles made today.
In conclusion, Gothic 2 exhibits remarkable attention to detail and dedication on the developer's part that makes this seemingly generic game shine like a supernova. And what little criticism it gets, is immediately quashed when I remember that Gothic 2's overall depth is almost unmatched by any game I have played before or since.
It's astounding that where so many mainstream studios have tried and failed for decades to produce something even remotely as interactive and immersive, a rather small and obscure European game company proves not only to be spectacularly successful, but also managed to produce one of the very best Role playing experiences ever made.