Commonly parties of adventurers in games are comprised of members so diverse that one has to wonder how they ever managed to gather up. Especially if the parties are pre-made by the plot (see JRPGs).
The most standard group of such is a wild barbarian or a soldier, a street urchin (thief), a well educated intellectual (mage), and one of extreme devotion to a god (priest) working together, even "adventuring" together.
You can find groups consisting of people who specialize in various aspects of the same thing, though mostly with soldiers where some function as archers and others as swordsmen. For anything else, the reasons needed to band such a group together become ever more fantastic. Usually one would see a group of soldiers accompanying few engineers or scientists (or mages/priests), but not few soldiers accompanied by few scientists and acrobats.
Many older games encourage creation of this type of groups, prepared for every eventuality as if such was
absolutely necessary. These same ones may make life difficult for players who try to build groups that are more consistent, such as a small squad of warriors backed by a battlemage, or even groups of single type of characters (e.g. band of thieves).
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