While the MM deals with giants in a very comprehensive
manner, just as there are many unusual people, there are many very unusual
giants. Norse giants are magically gifted races, and the most powerful have
clerical or illusionist powers, as well as magical weapons.

All of these giants are found in Jotunheim, which is directly attached to the planes
of Gladsheim. The giants of this land are crafty and ruthless when it comes to war,
but weak-willed and naive when it comes to everyday dealings
with giants of other types, gods, and men. They are known to sometimes
invite the gods to fun and games and will sometimes trade with them.

Many of the giants on the [Prime Material Plane] are descended from or
have contact with those of Jotunheim. This is particularly true in the case of
the frost and fire giants, who regard [Thrym] and [Surtur] as their leaders and
deities.

Quote:
Originally Posted by Gray Mouser
I agree. Can't recall any mythologies that have elves, dwarves, etc. as having the upper hand against humans.
Nor any fantasy literature, although I don't read as much of it as I used to.

Just so.
The Norse dwarves were like giants in their powers, and the French fey were as potent as fairies in some fairy tales.
Neither is suitable for inclusion as a character race in a FRPG.