In Texas, a man is startled when he sees a blue snake eating a rattlesnake. It is an indigo snake (Drymarchon Couperi) which is quite rare and lives in the Eastern u.s.. The indigo snake, It is a protected species and are harmless to humans, as it is non-venomous. Considered one of the largest snakes as they can reach the 2,60 meters in length, While it is immune to the venom of other snakes.