Rikki and Nag are both brave and stubborn.
Rikki and Nag are both animals behaving instinctively. Rikki-tikki-tavi is a mongoose, and a mongoose kills snakes. Snakes kill birds and try to defend themselves against mongooses and humans that might invade their territory.
Rikki and Nag both stand up to danger. Rikki is too curious to be afraid, and Nag is brave enough to stand up to Rikki and try to distract him so that Nagaina can sneak up on Rikki.
Nag was thinking to himself, and watching the least little movement in the grass behind Rikki-tikki. He knew that mongooses in the garden meant death sooner or later for him and his family, but he wanted to get Rikki-tikki off his guard. …
“Let us talk,'' he said. “You eat eggs. Why should not I eat birds?''
Rikki and Nag are both willing to put everything on the line for those that matter most to them. Rikki wants to defend the people in the bungalow, and Nag wants to defend his eggs.
Nag targets Rikki by trying to kill the people. Rikki is smart enough to know what he is planning, and finds him before he succeeds.
Nag coiled himself down, coil by coil, round the bulge at the bottom of the water-jar, and Rikki-tikki stayed still as death. After an hour he began to move, muscle by muscle, toward the jar. Nag was asleep, and Rikki-tikki looked at his big back, wondering which would be the best place for a good hold.
Rikki and Nag are both stubborn and resourceful. Each of them refuses to give up even when targeted by the other. Rikki wins because Nag relies too much on Nagaina and lets his guard down, while Rikki relies only on himself.
Rikki and Nag are a lot alike, and both of them are acting on instinct. Rikki's goal is to eliminate the threat of snakes, and Nag's is to protect his family. It is tempting to think of Nag and Nagaina as the villains, but we should also remember that Rikki and the people are the invaders.