Why did Nagania try to attack Rikki-tikki?
Nagaina wanted to get rid of Rikki-tikki because he was a threat to her family.
Nag and Nagaina were the cobras that lived in Rikki-tikki’s family garden. Nagaina tried to attack Rikki-tikki at several points during the story, because she knew that he was a great danger to her entire family. Nagaina had a group of eggs getting ready to hatch.
Nag tries to distract Rikki-tikki so that Nagaina can attack him.
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.
Rikki-tikki is too smart for this though. He turns just as Nagaina appears, because Darzee warns him that she is coming. He bites her, leaving her “torn and angry,” but it is a stalemate. Neither wins, and they must return to fight later.
After Rikki-tikki fights and kills Nagaina’s husband, Nag, she is even more desperate. When she learns that Rikki-tikki killed all of her eggs except one, she has no choice but to go after him. She wants to kill him, and save her baby.
Nagaina gathered herself together, and flung out at him. Rikki-tikki jumped up and backward. Again and again and again she struck, and each time her head came with a whack on the matting of the verandah, and she gathered herself together like a watch-spring.
Rikki-tikki had to put down the egg to fight her, so Nagaina took it and went into her hole. She was running for her life. It is very dangerous for a mongoose inside a cobra's hole, because she knows it better than he does, so she probably thought he would not follow. Rikki-tikki did follow her though, and killed her in the hole.