For an animal, trying to kill a snake is almost equal to suicide, but mongooses and meerkats have some advantages and tricks of their own.
Firstly, these little mammals live in a group of 10 to 40 mongooses, so surely it would be hard for the most tactical snake to handle so many mongoose at a time.
These mongooses have their own biological defense. Millions of years they have resided alongside snakes and they are rivals ever since the existence of the two. So, in course of time, mongoose adapted to snake venom. And today, one snake bite is not enough to kill them. It will require 2–4 bites to kill a healthy one. This is helpful in vs snake combats.
To kill the snake, the group of mongooses surround it and then try to close in from different directions. The snake is constantly distracted by the surrounding mongooses who try to bite it. Then, whenever any mongoose gets a chance to bite and jaw the distracted snake's mouth, it charges for the move. They always go for the face, so that they get a clutch on the snake most powerful weapon - its fangs. And if by chance its eyes are damaged, it is doomed for snake and celebration for the mongoose mob.
Of course, mongooses are not always the winners. Especially if its a superior species snake like king cobra - the longest venom snake or a Mozambique spitting cobra - who can spit venom in air from its fangs.