War Frogs

From the introduction: War Frogs! Okay. I really like these guys. They are nasty. Imagine living in a swampland. Horses and dogs are not effective in the soft and watery environment. Imagine a species of frog that is intelligent, can blend into the environment making it nearly invisible, navigate difficult terrain as easily as using a road and the ability to attack unwary victims with an acid attack. Yeah, the war frogs are calling.