What do Rikki and Nag have in common?
Although Nag is the antagonist and Rikki is the protagonist in "Rikki-Tikki-Tavi," they do have some similarities. They are both crafty, respectful of their adversaries, and determined.
Nag tries to deceive Rikki at their first meeting. He tilts his head and pretends he would like to get into a philosophical discussion about why eating birds is proper, but he is really trying to distract Rikki so Nagaina can strike. Likewise, Rikki is crafty with the snakes. For example, he enlists Darzee's wife to pretend she is lame to distract Nagaina while he destroys the eggs.
Nag is aware that "mongooses in the garden meant death sooner or later for him and for his family." Rikki is likewise aware of the power of his opponent. While planning how to attack Nag in the bathroom, Rikki says, "If I don't break his back at the first jump, he can still fight; and if he fights—O Rikki!" During the fight, he fully expects to die and is only saved by the man killing Nag with a gun.
Nag is determined to "kill the big man and his wife, and the child if I can." He allows his wife's talk of being "king and queen of the garden" to motivate him to do his deadly work. Similarly, Rikki is determined, but his goal is to save the humans and rid the garden of snakes. He makes sure Nag is killed first, then kills all but one of the baby snakes, and then he goes so far as to follow Nagaina down the rat hole, something very few mongooses would dare to do.
Nag and Rikki are well-matched adversaries, for each is crafty, respectful of his opponent, and determined to succeed with his plan.