Known as "the bounding elk," Uncas, son of Chingachgook, is an accomplished forester and warrior. He is the example of a "good Indian," given as a counterpoint to Magua as a "bad Indian." We're using bunny-ear quotes and the term "Indian" because Uncas is, in part, a stereotype. He's a good stereotype, sure, but he's a stereotype nonetheless.
We never see Uncas drink or manipulate people, and while Magua loves to give extemporaneous speeches, Uncas is reticent in the extreme, which makes his brief forays into the world of speech all the more touching. When a worried-sick Munro wants to get his daughter back, Uncas tells Munro: "Uncas will try."
Essentially, Uncas exhibits all the stereotypical elements of how a white person exoticizes Native Americans. He's like the "proud Indian" in a cheesy oil painting or decorative plate: he's strong and silent; he's attuned to the natural world in a way that is almost-but-not-quite magical; he has a strong moral compass; and, ultimately, he is too good for this world.
That's why he ends up dead, dead, dead.
But this stereotyping of Uncas doesn't mean he plays by white men's rules. His most stirring and impressive speech comes in Chapter 30 when he reveals his true identity as one of the last two surviving members of the Mohican tribe. He takes his rightful place among the Delaware, which is exciting, but we can't help but notice that he allows Cora (who he is in love with) to be taken away by Magua.
We don't think it's lack of romantic feeling that prompts him to do this, but rather his Native American sensibilities and principles. Over the course of the novel we see his astonishment at white behavior; allowing Magua to take Cora, then, in a sense reaffirms Uncas as placing his allegiance firmly with fellow Native Americans. He plays by the rules of Native American conduct and gives Magua a head start before pursuing him.