It would be a mistake to assume that the Changed are standard fantasy races. All of the Changed were human once, citizens of a technologically advanced society prone to cultural imperialism. Very few people chose consciously to become nonhumans. They evolved as their inner nature dictated rather than as their rational mind decided. These transformations are usually, but not always, permanent.
Some sweeping generalities about the different races are presented here. They are true in the general and false in the specific, like all generalities.
Your mileage may vary.
Dwarves appear in the dictionary next to the definitions for 'dour' and 'taciturn'. There have not been many dwarves sighted since the Change, mostly due to the fact that the vast majority of dwarves retreated underground and pulled together to form their own communities. Dwarves tend to have a good aptitude with technological sciences and are very likely to be able to keep modern technology alive and progressing in the years to come.
The few dwarves that are known about almost universally have engineering backgrounds and spend their days performing such vital tasks on equipment maintenance, vehicle repair, fuel production, and reloading ammo. Other dwarves are known for their feats of structural engineering, while still others excel at weaponsmithing and armoring. A very rare few are producing hand-crafted firearms that are of high enough quality to be enchanted. Such weapons are never for sale and are found primarily in the hands of the dwarven community defense forces.
Dwarves tend not to trust non-dwarves as a general rule, but are known to judge each individual on their own merits. Their gruff demeanor conceals an iron loyalty to those they consider friends. They don't truly hate any other race; they just don't have a whole lot of use for them. Any group invading one of their territories or attacking one of their settlements will be met with unbridled, unmerciful, unrelenting fury. It takes a lot to get a dwarf mad, but once that happens he or she will not stop until the offending party and anyone who protects them are dead. Other than that, dwarves are easy to get along with, and are always happy to raise a flagon with a friend.
There is no truth to the rumor that the jawas occasionally employed by the Overlords are in reality shaved dwarves. Female dwarves do not have beards. Anyone who tells you otherwise is setting you up for a rude reeducation (and a sound thrashing).
Standard 3E as per PHB
Fantasy gaming has characterized dark elves as being a treacherous, murderous, untrustworthy group of backstabbing, status-obsessed spider-worshipping vipers. This is, of course, complete rubbish: drow rarely worship spiders and are far more likely to manipulate you into getting yourself killed than they are to actually stab you themselves.
Drow are rarely kings and queens themselves; they much prefer the position of king-maker. Machiavelli, Neitzche, and Sun Tzu are honored teachers among the drow. Few publicly express any religious preference, though most are deeply religious.
Drow also present a unique case of sexual dimorphism. Only one drow male in ten is able to reproduce. These males are very tall and usually extremely muscular. Strong drow females are often forced to compete with one another over these fertile males.
The rest of the males are scrawny, weak-willed drones who live to be ordered around. Most of them used to be middle or upper management before the Change. When males of each type stand together, it looks like a live-action 'Charles Atlas' cartoon.
Alpha Male: +4 STR, +2 CON, -2 WIS, -2 CHR
Gold elves are usually the friendliest and most outgoing of the elven peoples. They are most likely to find themselves becoming ambassadors and go-betweens for the elven community and the outside world. Non-elves consider them to be more trustworthy than drow, nicer than moon elves, and less likely to stick a lance in your back than sylvan elves.
In the elven community, gold elves often serve as referees, counselors, advisors, and teachers. Many times, gold elves become very effective leaders in elven and non-elven communities alike.
The best gold elf leaders usually have a specific staff composition backing them: A drow policy advisor and political strategist; a moon elf religious or 'traditional culture' figure for moral guidance (whether real or not); and a sylvan elf "dustbuster" to take care of all the annoying little issues that leaders tend to encounter. Each advisor addresses things their people tend to be good at, leaving the gold elf leader free to concentrate on important matters like peace, prosperity, and the general welfare of his or her people.
Gold elves are mostly responsible for new art, music, and literature. They are very comfortable balancing elven and non-elven artforms and literary styles, often in ways that make moon elves cringe and wish desperately to be elsewhere. They are also capable of expressing a deeper range of passion and emotion in traditional artforms than any of the other subraces.
Gold elves are greatly connected to the land and are concerned with the welfare of their people to a greater extent than other elves. While the sylvan elves see themselves as guardians of the land, gold elves see themselves as caretakers of it.
+2 DEX, +2 INT, -2 STR, -2 CON
They see drow as being too willing to play "human mind games", and see gold elves as "assimilationists". They respect sylvan elves for their focus on elven matters, but see their occasional xenophobia as "unseemly" (they feel the same way; but to express it so openly is just not proper).
They would rather not have anything at all to do with non-elves, but will do so when required, albeit with much forced friendliness and a smile that looks like it's been painted on.
Although tempting, it is usually a bad idea to point out to a moon elf that the elven people really don't HAVE a culture, and that every elf on the planet was a human only a year or so ago. Moon elves consider that to be a mere technicality, and pointing it out is a grave insult to elven people everywhere. Elves do so have a culture; it has just been hidden for a long time and will require some effort to rediscover.
Standard 3E as per PHB
The defining characteristic of Sylvan elves is their xenophobia. They're not racists - they mistrust everybody. They won't simply kill you out of hand (usually!) - but they will only give you one warning shot before opening fire. They have no interest in the political machinations of other races - they themselves appoint, by acclaim, the most capable person to do a given job. They really don't understand why other races would make decisions any other way. The closest pre-Change description for their politics would be Democratic Socialism.
They see the elven place in the world as being an integral part of the natural order. Elvish purity requires a purely elvish environment. Elves are wild things and the further they are removed from the natural state, the less elvish they become. What most people think of as cities, they consider an abomination. This does not mean that they abhor technology unconditionally; they rather like automatic weapons and sophisticated sensor nets. They are eminently practical; as long as the technology exists, they're happy to use it on you.
As far as other elves go, they consider Drow to be hopelessly melodramatic
and completely untrustworthy. Their only use is keeping the 'round ears'
confused. Gold elves make concessions to the non-elven races far too easily.
The gold elven tendency to make peace with non-elves makes sylvan elves
highly uncomfortable, and gold elves are always regarded as slightly suspect
in their eyes. Moon elves are the most respected of the elven subraces,
but their obsession with culture, clothing and fine arts causes sylvan
elves to see them as effete snobs. Other races are not even as highly
thought of as the Drow - in fact, the sylvan elf word for 'non-elf' loosely
translates to 'target of opportunity.'
+2 STR, +2 DEX, -2 CON, -2 INT, -2 CHA
Homo Sapiens Sapiens. Curious little shaved monkeys. What's to know about them?
Humans make up about 55-60% of the total survivor population. Still very versatile and resourceful in emergencies. Equally skilled at warfare, magery, and the mind magics. Very diverse in belief, skill, knowledge, and worldview. Surviving humans tend to be more tolerant and open than nonhuman survivors, mostly due to the tendency for zealots and extremists to either get killed quickly or to Change.
There is a story, perhaps apocryphal, about an executive of the Ka Corporation who was assigned a Klingon as a bodyguard. The executive had been a copyright lawyer for Viacom before the Change. He looked his new bodyguard over for a minute, then turned to another executive and said, "I think their entire race could be considered our intellectual property. How much could the company make if we charged them a licensing fee to look like that?" They were still laughing when the bodyguard's betleH took their heads off. The official cause of death for both was listed as 'Suicide', and the bodyguard was reassigned to a senior executive who admired his initiative.
Klingons tend not to care about their race's origins - fictional is not so different from mythical, after all - unless it sounds like their honor is being slighted. Their response to that is both immediate and predictable.
Klingons tend to be stronger and hardier than humans. They have redundant organs and nerve systems, and an eight-chambered heart. This makes them very hard to kill, but it has a price, in the form of a biological drive towards action. They must always be DOING something. Klingons are not stupid, but they are impatient. They want results, not interminable research. The Klingon way is to watch for someone to develop something they want, and then take it from the inventor by conquest rather than build it themselves.
Klingon fighters may take the Rage feat as a bonus at first level. This feat is identical to the barbarian Rage ability.
+2 STR +2CON -1 INT -2 WIS -1 CHR